Publications

160. A General, Modular Access towards Immobilized Chiral Phosphoric Acid Catalysts and their Application in Flow Chemistry

M. Laue, M. Schneider, M. Gebauer, W. Böhlmann, R. Gläser, C. Schneider

Content: Chiral phosphoric acids (CPAs) are among the most frequently used organocatalysts with an ever-increasing number of applications. However, these catalysts are only obtained in a multi-step synthesis and are poorly recyclable, which significantly deteriorates their environmental and economic performance. We herein report a conceptually different, general strategy for the direct immobilization of CPAs on a broad scope of solid supports including silica, polystyrene and aluminum oxide. Solid-state catalysts were obtained in high yields and thoroughly characterized with elemental analysis by ICP-OES, nitrogen sorption measurements, thermo-gravimetric analysis, STEM/EDX images, and solid-state NMR spectroscopy. Further, the immobilized catalysts were applied to a variety of synthetically valuable, highly stereoselective transformations under batch and flow conditions including transfer hydrogenations, a Friedländer condensation/ transfer hydrogenation sequence and Mannich reactions under cryogenic flow conditions. Generally, high yields and stereoselectivities were observed along with a robust catalyst stability and reusability. After being used for 10 runs under batch conditions, no loss in selectivity or catalytic activity was observed. Under continuous flow conditions, the heterogeneous system was in operation for 19 hours and the high enantioselectivity remained unchanged throughout the entire process. We expect our approach to extend the applicability of CPAs to a higher level, with a focus on flow chemistry and a more environmentally friendly, resource-efficient use of these powerful catalysts. (Original title and abstract)

ACS Catal. 2024, 14, 5550-5559. Read The Publication

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159. Organocatalytic enantioselective oxa-Piancatelli rearrangement

R. Sarkar, A. Korell., C. Schneider

Content: The first highly enantioselective oxa-Piancatelli rearrangement has been developed. This process which is catalyzed by a chiral BINOL-derived phosphoric acid rearranges a wide range of furylcarbinols 1 into densely substituted γ-hydroxy cyclopentenones 2 in high yield with excellent diastereo- and enantioselectivities (up to 99 : 1 er). This reaction exhibits a high functional group tolerance and was applied to complex bioactive molecules as well. The products 2 were further manipulated into value-added molecular scaffolds further highlighting their versatility and synthetic utility. (Original title and abstract)

Chem. Commun. 2024, 60, 3063–3066. Read The Publication

158. Enantioselective (3+2)-Annulation of ß-Keto Esters with Azoalkenes towards Bicylic Dihydropyrroles via Cooperative Palladium and Brønsted Acid Catalysis

T. Friedmann, D. A. Mireles-Chávez, F. L. Walter, C. Schneider

Content: A cooperative catalytic process through Palladium and Brønsted acid activation has been developed for the conjugate addition of cyclic ß-keto esters 2 to azoalkenes 1 directly followed by hemiaminal formation upon cyclization. This transformation was enabled by utilizing chiral Pd-aqua complexes as combined Brønsted acid-base catalysts. Thus, bicyclic and highly functionalized dihydropyrroles 3 with two contiguous quaternary stereogenic centers were formed in excellent yields as single diastereomers and with exceptional enantioselectivity. (Original title and abstract)

Invited article as part of the thematic cluster "Chemical Synthesis and Catalysis in Germany"

Synlett 2024, 35, 997-1000. Read The PubliCation

157. Direct Access to 1,3-Oxathiolan-5-ones through (3+2)-Cycloaddition of Thioketones and Acetylenedicarboxylic Acid

F. Sachse, C. Schneider

Content: 1,3-Oxathiolan-5-ones are a hitherto very poorly studied class of sulfur heterocycles some of which have been shown to be important precursors for HIV drugs or bioactive, anticarcinogenic compounds. We have developed a novel and effective process for the direct generation of this structural motif in a (3+2)-cycloaddition of thioketones and acetylenedicarboxylic acid. The cycloadducts were obtained with complete regioselectivity and up to >99 % yield. The heterocyclic motif was confirmed by X-ray diffraction analysis. (Original title and abstract)

This manuscript is part of an Indo-German Workshop (IGW) special collection

Eur. J. Org. Chem. 2023, e202300834. Read this PubliCation

156. Brønsted Acid Catalyzed Asymmetric Synthesis of cis-Tetrahydrocannabinoids

C. Dorsch, C. Schneider

Content: We report herein the catalytic asymmetric cyclization of 1-aryl terpenols to afford enantiomerically highly enriched cis-tetrahydrocannabinoid scaffolds in a single step. As powerful chiral catalysts, strongly acidic imidodiphosphorimidates (IDPis) have been identified, which furnish the products with good yields and excellent enantioselectivity. Upon MOM-deprotection some naturally occurring cannabimimetica such as (–)-cis-Δ9-tetrahydrocannabinol and (–)-perrotettinene as well as some unnatural analogues were made accessible along a merely 3-step biomimetic sequence. (Original title and abstract)

Angew. Chem. 2023, e202302475. READ THIS PUBLICATION
Angew. Chem. Int. Ed. 2023, e202302475. Read THIS PUBLICATION

ChemRxiv, 2023. Read this PREPRINT Publication

Highlighted: in Synfacts 2023, 19, 0820. Read This Publication

Commented: in "Alkaloid Synthesis" (D. F. Taber) 2023. Read the Comment

Read the press release 2023/088 from 17/05/2023 of the University of Leipzig to ReSearchers Develop New Method to Synthesise Cannabis Plant Compound

155. New Developments of Chiral Palladium-Aqua Complexes as Cooperative Brønsted Acid-Base Catalysts in Organic Synthesis

C. Gärtner, C. Schneider

Content: Based upon their exceptional reactivity as cooperative Brønsted acid-base catalysts, chiral diphosphane Pd-aqua complexes have successfully been utilized in a broad range of asymmetric transformations. Originally discovered by Sodeoka 25 years ago, they readily form reactive chiral Pd enolates upon deprotonation of b-dicarbonyl compounds and simultaneously, a Brønsted acid liberated from the catalyst activates the electrophile. After the initial report and some ensuing papers had been published in the early 2000s, the field lay dormant for more than a decade. In recent years, however, new developments towards the enantioselective synthesis of various heterocycles and other useful compounds have evolved which take advantage of the unique properties of chiral Pd-aqua complexes. (Original title and abstract)

ChemCatChem 2023, e202300343. Read this PubliCation

154. Enantioselective 1,6-Addition of β-Ketoester Enolates to In Situ Generated para-Quinone Methides Enabled by Cooperative Palladium and Brønsted Acid Catalysis

C. V. Gärtner, C. Schneider

Content: We report herein an asymmetric cooperative process for the enantioselective 1,6-addition of β-ketoesters to in situ generated para-quinone methides with chiral Pd−aqua complexes as mixed Brønsted acid−base catalysts. Excellent yields, outstanding enantiocontrol, and good diastereoselectivity across a broad substrate range are highlights of this transformation. The utility of this reaction is further demonstrated by a facile scale up and subsequent complexity-increasing modifications. (Original title and abstract)

Org. Lett. 2023, 25, 416-420. Read this PubliCation

153. New developments in enantioselective Brønsted acid catalysis with strong hydrogen-bond donors in Asymmetric Organocatalysis: New Strategies, Catalysts, and Opportunities

C. Dorsch, C. Schneider

Content: The last 2 decades have seen a surge of publications in the area of chiral Brønsted acid catalysis. Starting primarily from the seminal contributions of Akiyama and Terada on BINOL-phosphoric acids, this and related chiral motifs have steadily been modified and improved into ever more acidic and at the same time more selective chiral catalysts. Almost any reaction which is subject to acid catalysis can nowadays be executed in an enantioselective fashion with good levels of enantiocontrol. While the original Akiyama/Terada catalysts were largely limited to basic substrates such as imines, the newer catalysts described in this chapter can easily activate regular carbonyl substrates, alcohols, and even olefins. Previous limitations resulting from high catalyst loadings and problems with upscaling have largely been overcome with the newest generation of super-acidic Brønsted acid catalysts which frequently work at catalyst loadings of as low as 0.01 mol% effectively competing with the most powerful metal catalysts. (Original title and abstract)

(L. Albrecht, Ed.), Wiley-VCH 2023, 1, 3-42, Online ISBN: 9783527832217, DOI:10.1002/9783527832217.

152. Enantioselective [6+2]-Cycloaddition of Transient 3-Methide-3H-pyrroles with 2-Vinylindoles under Chiral Brønsted Acid Catalysis

R. Sarkar, I. Kallweit, C. Schneider

Content: An organocatalytic, highly diastereo- and enantioselective [6 + 2]-cycloaddition of 3-methide-3H-pyrroles with 2-vinylindoles has been developed. This BINOL phosphoric acid-catalyzed reaction utilizes pyrrole-3-carbinols as precursors for the in situ generation of 3-methide-3H-pyrroles to access densely substituted cyclopenta[b]pyrroles bearing three contiguous stereogenic centers as single diastereomers in good yields with excellent enantioselectivity. (Original title and abstract)

Org. Lett. 2022, 24, 6433–6437. Read this PubliCation

151. An Integrated Resource-Efficient Microfluidic Device for Parallelised Studies of Immobilised Chiral Catalysts in Continuous Flow via Miniaturized LC/MS-analysis

H. Westphal, R. Warias, C. Weise, D. Ragno, H. Becker, M. Spanka, A. Massi, R. Gläser, C. Schneider, D. Belder

Content: A highly integrated microfluidic device is presented for the parallelized study of stereoselective heterogeneous catalytic processes. For the first time, multiple packed-bed μ-flow reactors are combined with a chiral separation unit on a chip that is seamlessly connected to mass spectrometry. By developing an automated fluidic setup, this device allows the performance of different catalysts to be studied in a single run, using only small amounts of resources. In this way, fully automated quasi-simultaneous testing of 2-packed bed reactors for enantioselectivity and conversion is possible, with a significant reduction in solvent and substrate consumption compared to classical tube reactor HPLC-MS testing. (Original title and abstract)

React. Chem. Eng., 2022, 7, 1936-1944. Read this PubliCation

150. Enantioselective Annulation of α,β-Unsaturated N-Acyliminium Ions with β-Keto Ester Enolates via Cooperative Palladium/Brønsted Acid Catalysis

C. V. Gärtner, C. Schneider

Content: We herein report a cooperative Palladium/Brønsted acid catalyzed strategy towards the first enantioselective annulation of in situ generated α,β-unsaturated N-acyliminium ions with chiral metal enolates. Novel polycyclic oxoisoindoles featuring three contiguous stereogenic centers have been obtained with typically good yields, outstanding enantiocontrol and moderate to good diastereoselectivity. The utility of the process was further demonstrated by their conversion into synthetically valuable scaffolds (Original title and abstract)

Org. Lett. 2022, 24, 3560-3564. Read this PubliCation

149. Cooperative Palladium/Brønsted Acid Catalysis Towards the Highly Enantioselective Allenylation of ß-Keto Esters.

H. J. Loui, C. Schneider

Content: We report the first enantioselective allenylation of Pd enolates enabled by cooperative Pd/Brønsted acid catalysis employing β-keto esters and propargyl alcohols. The enantioselectivity originates solely from an in-situ-generated chiral metal enolate in an open transition state with no additional binding of the propargyl component to the catalyst. Thus, a broad substrate scope was established, furnishing hitherto inaccessible products in very good yields with excellent enantioselectivities (up to >99:1 e.r.). (Original title and abstract)

Org. Lett. 2022, 24, 1496-1501. Read this PubliCation

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148. Asymmetric Brønsted Acid-Catalyzed Cycloadditions of Ortho-Quinone Methides and Related Compounds (Review).

C. Dorsch, C. Schneider

Content: This review summarizes recent developments in the area of Brønsted acid-catalyzed, enantioselective cycloadditions of ortho-quinone methides, ortho-quinone methide imines as well as heterocyclic indole- and pyrrol-based methides. In a straightforward and single-step transformation complex polycyclic N- and O-heterocyclic scaffolds are accessible with typically good yields and excellent stereocontrol from simple benzyl and heterobenzyl alcohols upon acid-catalyzed dehydration. The transient precursors are hydrogen-bonded to a chiral Brønsted acid which controls the enantioselectivity of the process. (Original title and abstract)

Synthesis 2022, 54, 3125-3141. Read this PubliCation

147. Asymmetric Synthesis of Fused Tetrahydroquinolines via Intramolecular Aza-Diels-Alder Reaction of ortho-Quinone Methide Imines.

F. Hofmann, C. Gärtner, M. Kretzschmar, C. Schneider

Content: Aza-Diels Alder reactions are straightforward processes in the construction of N-heterocycles, featuring inherent atom-economy and stereospecificity. Intramolecular strategies allow formation of bicyclic core structures with up to three stereocenters within a single step. Herein, this concept is combined with the chemistry of chiral Brønsted acid-bound ortho-quinone methide imines generating a range of interesting fused tetrahydro-quinolines in a diastereo- and enantioselective manner. (Original title and abstract)

Synthesis 2022, 54, 1055-1080. Read this PubliCation

146. Brønsted Acid Catalyzed (3+2)-Cycloaddition of Thioketones and Indole-2-Carbinols Toward Thiazolo[3,4-a]indoles.

F. Sachse, C. Schneider

Content: Herein, we report a Brønsted acid catalyzed approach to access the yet unknown heterocyclic motif of thiazolo[3,4-a]indoles in a one-pot reaction under very mild conditions. A broad range of thiazolo[3,4-a]indoles was generated from indole-2-methanols and thioketones with 45-99% yield and good functional group tolerance.The practicality of the process and the synthetic potential of  the  products  were  demonstrated  with  an  upscaling experiment  and  further  transformations.  Additional control experiments provided mechanistic insights into this cycloaddition (Original title and abstract)

Adv. Synth. Catal. 2022, 364, 77-81. Read this PubliCation

145. Stereoselective Synthesis of the Decahydroquinoline Alkaloid cis-195J.

R. Veliu, C. Schneider

Content: The first enantioselective synthesis of two C-5 diastereomers of the proposed structure of the decahydroquinoline alkaloid cis-195J has been achieved. The key step of our strategy is the highly stereoselective vinylogous Mukaiyama–Mannich reaction (VMMR), which gave rise to the first two stereogenic centers at the ring fusion with excellent diastereo- and enantiocontrol. Through alkyne cyclization and enamine reduction the correct cis-configuration between C-2, C-4a, and C-8a in the decahydroquinoline backbone was established. Subsequently, a radical cyclization of a tethered alkyl iodide onto the enoate assembled the bicyclic cis-decahydroquinoline as a mixture of two C-5 diastereomers. Further elaboration of the C-5 side chain eventually provided both diastereomers of cis-195J, which were readily separated, and their constitution and configuration were thus unambiguously proven for the first time. (Original titel and abstract)

J. Org. Chem. 2021, 86, 11960–11967. Read this PubliCation

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144. Unveiling Organocatalysts Action – Investigating Immobilized Catalysts at Steady-State Operation via Lab-on-a-Chip Technology

H. Westphal, R. Warias, H. Becker, M. Spanka, D. Ragno, R. Gläser, C. Schneider, A. Massi, D. Belder

Content: This paper reports a new method for studying stereoselective catalyzed reactions at a small scale. For this purpose, a micro-sized chemical reactor and a chiral chromatographic column were integrated on a single microfluidic chip hyphenated to mass spectrometry. By running the integrated reactor in truly continuous-flow operation with an automated injection strategy, catalytic processes and their stereoselectivity can be observed over an extended range of time with significantly small consumption of samples, solvents, and catalytic material. (Original titel and abstract)

ChemCatChem. 2021, 13, 5089-5096. Read this PubliCation

143. Cooperative Photoinduced/Brønsted Acid Catalyzed Cycloaddition of Transient Thioaldehydes and ortho-Quinone Methides toward a Synthesis of Benzo[e][1,3]oxathiines.

F. Sachse, C. Schneider

Content: A cooperative, one-pot approach for the in situ generation and ensuing cycloaddition of thioaldehydes and ortho-quinone methides transiently formed under irradiation with UV-A light and Brønsted acid catalysis, respectively, has been developed giving direct access to benzo[e][1,3]oxathiines in good to excellent yields and diastereoselectivity. Both electron-rich and electron-poor thioaldehydes easily react with a broad range of ortho-quinone methides at ambient temperature in a short reaction time to furnish a wide variety of S,O-heterocycles. (Original titel and abstract)

Org. Lett. 2021, 23, 2682–2686. Read this PubliCation

142. Cooperative Rh/Chiral Phosphoric Acid Catalysis toward the Highly Stereoselective (3+3)-Cycloannulation of Carbonyl Ylides and Indolyl-2-methides.

H. J. Loui, A. Suneja, C. Schneider

Content: A stereoselective (3+3)-cycloannulation of in situ generated carbonyl ylides with indolyl-2-methides has been developed furnishing oxa-bridged azepino[1,2-a]indoles within one synthetic step. This process is enabled by cooperative rhodium and chiral phosphoric acid catalysis to produce both transient intermediates in separate catalytic cycles. The products comprising three stereogenic centers were obtained with good stereoselectivity and yields and display valuable heterocyclic complexity. (Original titel and abstract)

Org. Lett. 2021, 23, 2578–2583. Read this Publication

141. Continuous Flow Synthesis of 2H‐Thiopyrans via thia‐Diels–Alder Reactions of Photochemically Generated Thioaldehydes.

F. Sachse, K. Gebauer, C. Schneider

Content: 3,6‐Dihydro‐2H‐thiopyrans are important structural motifs both in organic synthesis and medicinal chemistry. A continuous flow‐process for the photochemical generation of thioaldehydes from phenacyl sulfides and the ensuing [4+2]‐cycloaddition with electron‐rich 1,3‐dienes was developed. The cycloadducts were obtained with excellent yields in short reaction times and much improved productivities as compared to classical batch reactions. (Original titel and abstract)

Eur. J. Org. Chem. 2021, 1, 64-71. Read This Publication

Find out more about Christoph Schneider in his Author Profile.

Angew. Chem. 2020, 132, 21462. Read This Publication
Angew. Chem. Int. Ed. 2020, 59, 21278. Read This Publication.

139. Brønsted-Acid-Catalyzed (3+2)-Cycloannulation of In-Situ-Generated 3-Methide-3H-pyrroles: Asymmetric Synthesis of Cyclopenta[b]pyrroles.

I. Kallweit, M. Laue, C. Schneider

Content: An organocatalytic, highly enantioselective addition of cyclic enamides to in-situ-generated 3-methide-3H-pyrroles with subsequent cyclization and elimination has been developed. This protocol represents a novel and straightforward route toward polycyclic cyclopenta[b]pyrroles with high yields and excellent enantioselectivity. Central to the success is the formation of a chiral, hydrogen-bonded 3-methide-3H-pyrrole upon phosphoric-acid-catalyzed dehydration of the starting 1H-pyrrol-3-yl carbinol that reacts with the enamide in a stepwise cycloannulation process. (Original title and abstract)

Org. Lett. 2020, 22, 9065–9070. Read this Publication

138. Short Synthesis of Alkaloid (−)-205B.

M. Tripathy, C. Schneider

Content: The alkaloid (−)-205B has in the past served as a testing ground for novel approaches in nitrogen heterocycle synthesis. We herein report a highly straightforward synthesis of (−)-205B in just six synthetic steps, making it the shortest route currently known. The central steps of our approach are a vinylogous Mukaiyama–Mannich reaction to establish the first two stereogenic centers with excellent diastereo- and enantiocontrol followed by zinc-mediated Barbier allylation to set the third chiral center with high substrate control. Upon cyclization of the Barbier product to lactam and enolate methylation, the third ring is annulated by a one-pot sequence of lactam reduction and aza-Prins cyclization to directly set the final stereogenic center with complete cis-stereoselectivity. As the iminium ion undergoing the aza-Prins cyclization rapidly isomerized to a planar enamine intermediate, the alkaloid was eventually obtained as a 1:1 mixture of C6 diastereomers, which were readily separated by chromatography. Yet, the target natural product was obtained isomerically pure in an overall yield of 12%, which compares favorably with all previous syntheses. (Original title and abstract)

J. Org. Chem. 2020, 85, 12724-12730. Read this Publication

Excellent: Among the top 20 of most downloaded papers published in J.­ Org.­ Chem. in September 2020

137. Palladium-Catalyzed, Enantioselective (3+2)-Cycloannulation of β-Keto Esters with Alkylidene 2H-Indoles toward Complex Indole-Based Heterocycles.

F. Göricke, C. Schneider

Content: A cooperative approach toward biologically important N-fused polycyclic indoles with synthetically challenging tetracyclic [6–5–5–6] and [6–5–5–5] core structures has been developed. The concept is based on a highly stereoselective (3 + 2)-cycloannulation of chiral metal enolates with a reactive vinylogous iminium ion, both generated in situ via dual activation with a single chiral Pd catalyst (5 mol %). Densely functionalized pyrrolo[1,2-a]indoles with three contiguous chiral centers were constructed with high stereoselectivities (>95:5 d.r. and up to >99% ee) and excellent yields (up to 99%). ESI-MS studies and additional control experiments provided a clear mechanistic picture of the cycloannulation event. The products were readily transformed into an array of valuable, indole-based, highly complex heterocycles. (Original title and abstract)

Org. Lett. 2020, 22, 6101-6106. Read this Publication

136. Phosphoric Acid Catalyzed Formation of Hydrogen-Bonded o-Quinone Methides. Enantioselective Cycloaddition with β-Dicarbonyl Compounds toward Benzannulated Oxygen Heterocycles.

F. Göricke, S. Haseloff, M. Laue, M. Schneider, T. Brumme, C. Schneider

Content: A full account of the Brønsted acid catalyzed, enantioselective synthesis of 4H-chromenes and 1H-xanthen-1-ones from o-hydroxybenzyl alcohols and β-dicarbonyl compounds is provided. The central step of our strategy is the BINOL–phosphoric acid catalyzed, enantioselective cycloaddition of β-diketones, β-keto nitriles, and β-keto esters to in situ generated, hydrogen-bonded o-quinone methides. Upon acid-promoted dehydration, the desired products were obtained with generally excellent yields and enantioselectivity. Detailed mechanistic studies including online-NMR and ESI-MS measurements were conducted to identify relevant synthetic intermediates. A reversible formation of a dimer from the starting alcohol and the reactive o-quinone methide in an off-cycle equilibrium was observed, providing a reservoir from which the o-quinone methide can be regenerated and introduced into the catalytic cycle again. Reaction progress kinetic analysis was utilized to determine kinetic profiles and rate constants of the reaction uncovering o-quinone methide formation as the rate-limiting step. In combination with Hammett plots, these studies document the relationship between o-quinone methide stabilization by electronic effects provided by the substituents and the reaction rate of the described process. In addition, DFT calculations reveal a concerted yet highly asynchronous [4 + 2]-cycloaddition pathway and an attractive CH−π interaction between the catalyst’s tBu group and the o-quinone methide as an important stereochemical control element. (Original title and abstract)

J. Org. Chem. 2020, 85, 11699-11720. Read this publication

134. Unravelling the configuration of transient ortho-quinone methides by combining microfluidics with gas phase vibrational spectroscopy.

M. Mayer, M. Pahl, M. Spanka, M. Grellmann, M. Sickert, C. Schneider, K. R. Asmis, D. Belder

Content: The alkylidene double bond configuration of transient ortho-quinone methides (o-QMs) is studied by cryogenic ion trap vibrational spectroscopy. To this end, o-QMs are formed from ortho-hydroxy benzhydryl alcohols in a Brønsted acid mediated dehydration reaction on a microfluidic chip reactor and the E/Z isomer ratio is determined by comparing the measured gas phase mid-infrared fingerprints with the predicted harmonic spectra from density functional theory calculations. Control over the stereochemistry is achieved by exploiting steric repulsion interactions between the substituents adjacent to the formal double bond of the o-QMs. Attempts to manipulate the ratio of the E- and Z-isomers by varying the reaction conditions were unsuccessful. This observation suggests a low isomerization barrier and hence shorter equilibration times with respect to the on-chip residence time. The fluxional character of the formal double bond is confirmed in ¹³C-labelling experiments, which reveal a substantially red-shifted CC stretching frequency characteristic for extended, conjugated π-systems. (Original title and abstract)

Phys. Chem. Chem. Phys. 2020, 22, 4610-4616. Read this publication

133. Cooperative Catalysis for the Highly Diastereo‐ and Enantioselective [4+3]‐Cycloannulation of ortho‐Quinone Methides and Carbonyl Ylides.

A. Suneja, H. J. Loui, C. Schneider

Content: We describe herein a highly diastereo‐ and enantioselective [4+3]‐cycloannulation of ortho‐quinone methides and carbonyl ylides to furnish functionalized oxa‐bridged dibenzooxocines with excellent yields and stereoselectivity in a single synthetic step. The combination of rhodium and chiral phosphoric acid catalysis working in concert to generate both transient intermediates in-situ provides direct access to complex bicyclic products with two quaternary and one tertiary stereogenic centers. The products may be further functionalized into valuable and enantiomerically highly enriched building blocks. (Original title and abstract)

Angew. Chem. 2020, 132, 5580-5585. Read this publication
Angew. Chem. Int. Ed. 2020, 59, 5536-5540. Read this publication

132. Brønsted Acid-Catalyzed, Diastereo- and Enantioselective, Intramolecular Oxa-Diels–Alder Reaction of ortho-Quinone Methides and Unactivated Dienophiles.

R. Ukis, C. Schneider

Content: A stereoselective, phosphoric acid-catalyzed synthesis of dihydrochromenochromenes has been developed using transient ortho-quinone methides (o-QMs). Three contiguous stereogenic centers were formed with excellent yields, partially as single diastereomers and with moderate to excellent enantioselectivity. This intramolecular hetero-Diels–Alder reaction features unactivated dienophiles and o-QM precursors tethered by a simple phenoxy linker and furnishes cycloadducts with a prominent structural motif found in many natural products. Through an appropriate choice of dienophile configuration and backbone substitution either exo- or endo-stereoisomers were formed selectively with up to a 96:04 enantiomeric ratio. (Original title and abstract)

J. Org. Chem. 2019, 84, 7175-7188. Read this publication

131. Continuous Flow Synthesis of Highly Substituted Tetrahydrofurans.

P. Hoffmeyer, C. Schneider

Content: The highly diastereoselective synthesis of multiply substituted tetrahydrofurans was achieved in a sequential process under continuous flow conditions. Greatly reduced reaction times, improved selectivities and enhanced yields are the benefits of this approach in comparison to the initial batch synthesis. Moreover, gram amounts of product were produced in the flow reactor likewise due to facile upscaling. In addition, employing a novel bis(silyl)dienediolate tetrasubstituted tetrahydrofurans were made accessible as well. (Original title and abstract)

Eur. J. Org. Chem. 2019, 5326-5333. Read This Publication

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130. Iron(III)-Catalyzed (4 + 2)-Cycloannulation of 2-Hydroxy Ketoxime Ethers with Indol-2-ylamides: Synthesis of Indole-Fused 2-Piperidinones.

M. Schlegel, C. Schneider

Content: A highly regio- and diastereoselective (4 + 2)-cycloannulation process of indanone-derived 2-hydroxy ketoxime ethers with 1,4-bisnucleophilic indol-2-ylamides has been developed. In the presence of 5 mol % FeCl₃, densely functionalized 2-piperidinones containing two new σ-bonds and two vicinal quaternary stereogenic centers were formed under mild reaction conditions in a one-pot operation. Moreover, most of the products directly precipitated out of the solution and were isolated by simple filtration without purification by column chromatography. (Original title and abstract)

J. Org. Chem. 2019, 84, 5886-5892. Read This Publication

129. Brønsted Acid Catalyzed [6 + 2]-Cycloaddition of 2-Vinylindoles with in Situ Generated 2-Methide-2H-pyrroles: Direct, Catalytic, and Enantioselective Synthesis of 2,3-Dihydro-1H-pyrrolizines.

I. Kallweit, C. Schneider

Content: We describe herein an organocatalytic, diastereo- and enantioselective [6 + 2]-cycloaddition toward the synthesis of densely substituted 2,3-dihydro-1H-pyrrolizines bearing three contiguous stereogenic centers which are obtained with good yields, as single diastereomers, and with excellent enantioselectivity. A crucial feature of this one-step process leading to a prominent structural motif in many biologically active natural products is a BINOL-derived phosphoric acid catalyzed reaction of 1H-pyrrole-2-yl carbinols with 2-vinylindoles via the corresponding hydrogen-bonded chiral 2-methide-2H-pyrroles. (Original title and abstract)

Org. Lett. 2019, 21, 519-523. Read This Publication

128. Stereoselective Synthesis of 2,3,5-Trisubstituted Tetrahydrofurans Initiated by a Titanium–BINOLate-Catalyzed Vinylogous Aldol Reaction.

P. Hoffmeyer, C. Schneider

Content: The enantioselective synthesis of 2,3,5-trisubstituted tetrahydrofurans 3 has been achieved using a chiral titanium–BINOL complex as catalyst for the vinylogous Mukaiyama aldol reaction of bis(silyl) diendiolate 1 and an aldehyde. The ensuing BF₃·OEt₂-mediated Prins-type cyclization with a second aldehyde gave rise to 2,3,5-substituted tetrahydrofurans 3 with generally good yields and excellent stereocontrol. In this process, three new σ-bonds and three new stereogenic centers were generated in a one-pot process. (Original title and abstract)

J. Org. Chem. 2019, 84, 1079-1084. Read This Publication

127. Phosphoric Acid Catalyzed [4 + 1]-Cycloannulation Reaction of ortho-Quinone Methides and Diazoketones: Catalytic, Enantioselective Access toward cis-2,3-Dihydrobenzofurans.

A. Suneja, C. Schneider

Content: A highly straightforward route to enantiomerically highly enriched cis-2,3-dihydrobenzofurans has been achieved via addition of α-diazocarbonyl compounds to in situ generated o-QMs catalyzed by a chiral Brønsted acid. This catalytic strategy provides a direct access to 2,3-dihydrobenzofurans in high yields and with up to 91:9 d.r. and 99:1 e.r. at ambient temperature. Moreover, a unique phenonium-type rearrangement accounts for product formation with an inverted 2,3-substitution pattern. (Original titel and abstract)

Org. Lett. 2018, 20, 7576-7580. Read This Publication

126. Palladium‐Catalyzed Enantioselective Addition of Chiral Metal Enolates to In Situ Generated ortho‐Quinone Methides

F. Göricke, C. Schneider

Content: We describe herein a conceptually novel, cooperative Brønsted acid/base catalyzed process for the conjugate addition of cyclic β‐keto esters to ortho‐quinone methides both generated in situ. Upon hemiacetalization, densely functionalized chiral chromans with two adjacent quaternary and additionally a tertiary stereogenic center were obtained with very good diastereoselectivity (up to >95:5 d.r.) and typically excellent enantioselectivity (up to >99 % e.e.). The striking feature and key to success is the dual catalytic activation of both nucleophile and electrophile in two separate cycles with a single chiral catalyst. (Original title and abstract)

Angew. Chem. 2018, 130, 14952-14957. Read ThIs Publication
Angew. Chem. Int. Ed. 2018, 57, 14736-14741. Read This Publication

Excellent: Among the top 10% most downloaded papers published in Angew. Chem./Angew. Chem. Int. Ed. from December 2018 to January 2019

Highlighted: in Synfacts 2019, 15, 0056. Read This Highlight

125. A Highly Enantio‐ and Diastereoselective Synthesis of Spirocyclic Dihydroquinolones via Domino Michael Addition‐Lactamization of ortho‐Quinone Methide Imines.

T. Hodik, C. Schneider

Content: Spirocyclic dihydroquinolones have been obtained with good yields and excellent diastereoselectivity (>20:1 d.r.), and enantioselectivity (up to 99:1 e.r.) from in situ generated ortho‐quinone methide imines and cyclic β‐oxo esters. This one‐step domino Michael addition–lactamization process features mild reaction conditions, easily accessible starting materials, and products with two adjacent chiral centers one of which is quaternary. Mechanistic studies revealed the in situ generated chiral magnesium phosphate salt rather than the free phosphoric acid to be the more reactive catalyst for this reaction. (Original title and abstract)

Chem. Eur. J. 2018, 24, 18082-18088. Read This Publication

Excellent: Among the top 10% most downloaded papers published in Chem. Eur. J. from December 2018 to January 2019

124. Lewis acid-catalyzed Friedel–Crafts reactions toward highly versatile, α-quaternary oxime ethers.

M. Schlegel, C. Schneider

Content: The synthesis of all-carbon-substituted, quaternary stereocenters through Lewis acid-catalyzed Friedel–Crafts alkylation of cyclic and acyclic 2-hydroxy oxime ethers proceeds under mild reaction conditions and with high yields. Moreover, the oxime ether moiety can be easily manipulated into various functional groups through subsequent modifications. (Original title and abstract)

Chem. Commun. 2018, 54, 11124-11127. Read This Publication

123. Phosphoric Acid Catalyzed Aldehyde Addition to in Situ Generated o-Quinone Methides: An Enantio- and Diastereoselective Entry toward cis-3,4-Diaryl Dihydrocoumarins.

M. Spanka, C. Schneider

Content: A highly stereoselective, phosphoric acid catalyzed synthesis of cis-3,4-diarylchromanols through reaction of o-hydroxybenzhydryl alcohols and aryl acetaldehydes is reported. The products can be further manipulated to 3,4-dihydrocoumarins, 4H-chromenes, and chromanes with good overall yields and very good diastereo- and enantiocontrol. This reaction is based upon the concept of enol catalysis and comprises the in situ generation of hydrogen-bonded o-quinone methides and their formal [4 + 2]-cycloaddition with aldehyde enols. (Original title and abstract)

Org. Lett. 2018, 20, 4769-4762. Read This Publication

Highlighted: in Synfacts 2018, 14, 1090. Read This Highlight

122. Novel Sc(OTf)₃‐Catalyzed (2+2+1)‐Cycloannulation/Aza‐Friedel–Crafts Alkylation Sequence toward Multicyclic 2‐Pyrrolines.

M. Schlegel, P. Coburger, C. Schneider

Content: The rapid assembly of molecular complexity continues to be at the forefront of novel reaction development. In the pursuit of that goal, we herein report a novel Sc(OTf)₃‐catalyzed, one‐pot multicomponent reaction that furnishes complex multicyclic 2‐pyrrolines with excellent overall yields and perfect diastereocontrol. This process is based on our previously established (2+2+1)‐cycloannulation of in situ generated 1‐azaallyl cations, 1,3‐dicarbonyls and primary amines. The newly formed and highly reactive aminal moiety is readily substituted with indoles and pyrroles both as external and internal π‐nucleophiles to provide densely functionalized N‐heterocycles with four new σ‐bonds and two vicinal quaternary stereogenic centers. In addition, DFT calculations have been conducted to further characterize the intermediate 1‐azaallyl cations. (Original title and abstract)

Chem. Eur J. 2018, 23, 14207-14212. Read This Publication

121. Rapid Construction of Complex 2-Pyrrolines through Lewis Acid-Catalyzed, Sequential Three-Component Reactions via in Situ-Generated 1-Azaallyl Cations.

M. Schlegel, C. Schneider

Content: The first Sc(OTf)₃-catalyzed dehydration of 2-hydroxy oxime ethers to generate benzylic stabilized 1-azaallyl cations, which are captured by 1,3-carbonyls, is described. A subsequent addition of primary amines in a sequential three-component reaction affords highly substituted and densely functionalized tetrahydroindeno[2,1-b]pyrroles as single diastereomers with up to quantitative yield. Thus, three new σ-bonds and two vicinal quaternary stereogenic centers are generated in a one-pot operation. (Original title and abstract)

Org Lett. 2018, 20, 3119-3123. Read This Publication

120. Intramolecular Aza‐Diels–Alder Reactions of ortho‐Quinone Methide Imines: Rapid, Catalytic, and Enantioselective Assembly of Benzannulated Quinolizidines.

M. Kretzschmar, F. Hofmann, D. Moock, C. Schneider

Content: Aza‐Diels–Alder reactions (ADARs) are powerful processes that furnish N‐heterocycles in a straightforward fashion. Intramolecular variants offer the additional possibility of generating bi‐ and polycyclic systems with high stereoselectivity. We report herein a novel Brønsted acid catalyzed process in which ortho‐quinone methide imines tethered to the dienophile via the N substituent react in an intramolecular ADAR to form complex quinolizidines and oxazinoquinolines in a one‐step process. The reactions proceed under very mild conditions, with very good yields and good to very good diastereo‐ and enantioselectivities. Furthermore, the process was extended to a domino reaction that efficiently combines substrate synthesis, ortho‐quinone methide imine formation, and ADAR. (Original titel and abstract)

Angew. Chem. 2018, 130, 4864-4868. Read This Publication
Angew. Chem. Int. Ed. 2018, 57, 4774-4778. Read This publication

119. Modular Synthesis of Dipyrroloquinolines: A Combined Synthetic and Mechanistic Study.

J. Appun, F. Stolz, S. Naumov, B. Abel, C. Schneider

Content: A straightforward synthesis of [1,2-a][3′,2′-c]dipyrroloquinolines has been developed generating up to eight new σ-bonds and five new stereogenic centers in a simple and modular one-pot operation. Generally good to excellent yields and moderate to good stereoselectivities in favor of the all-cis stereoisomer were observed. A detailed investigation combining synthetic studies, analytical measurements, and theoretical calculations has been conducted to elucidate the reaction mechanism using ESI- and liquid-beam IR-laser desorption mass spectrometry as well as DFT calculations. Key steps of this sequential transformation include a Lewis acid-catalyzed vinylogous Mukaiyama–Mannich reaction of bis(silyl) dienediolate 1 and a Brønsted acid-promoted Mannich–Pictet–Spengler reaction cascade reaction to complete the synthesis of the dipyrroloquinoline core of the target compounds. (Original title and abstract)

J. Org. Chem. 2018, 83, 1737-1744. Read This Publication

118. Continuous purification of reaction products by micro free-flow electrophoresis enabled by large area deep-UV fluorescence imaging.

S. A. Pfeiffer, B. M. Rudisch, P. Glaeser, M. Spanka, F. Nitschke, A. A. Rubitzki, C. Schneider, S. Nagl, D. Belder

Content: Microreactors have gained increasing attention in their application toward continuous micro flow synthesis. An unsolved problem of continuous flow synthesis is the lack of techniques for continuous product purification. Herein, we present a micro free-flow electrophoresis device and accompanying setup that enables the continuous separation and purification of unlabeled organic synthesis products. The system is applied to the separation and purification of triarylmethanes. For imaging of the unlabeled analytes on-chip a novel setup for large area (3.6 cm²) deep ultra violet excitation fluorescence detection was developed. Suitable separation conditions based on low conductivity electrophoresis buffers were devised to purify the product. With the optimized conditions, starting materials and product of the synthesis were well separated (R > 1.2). The separation was found to be very stable with relative standard deviations of the peak positions smaller than 3.5% over 15 min. The stable conditions enabled collection of the separated compounds, and purity of the product fraction was confirmed using capillary electrophoresis and mass spectrometry. This result demonstrates the great potential of free-flow electrophoresis as a technique for product purification or continuous clean-up in flow synthesis. (Original title and abstract)

Anal. Bioanal. Chem. 2018, 410, 853-862. Read This Publication

• C. Schneider, M. Sickert

"The Mannich Reaction"
Science of Synthesis Knowledge Updates (M. Christmann, Ed.), Georg Thieme Verlag KG 2017/3, 315.
ISBN: 978-3-13-241419-8
DOI: 10.1055/sos-SD-140-00225

• K. Gebauer, F. Reuß, M. Spanka, C. Schneider

"Relay Catalysis: Manganese(III) Phosphate-Catalyzed Asymmetric Addition of β-Dicarbonyls to ortho-Quinone Methides Generated by Catalytic Aerobic Oxidation"
Org. Lett. 2017, 19, 4588-4591.
Highlighted in Synfacts 2018, 14, 63.

• J. Appun, M. Boomhoff, P. Hoffmeyer, I. Kallweit, M. Pahl, D. Belder, C. Schneider

"A New and Highly Stereoselective Synthesis of Tetrahydrofurans"
Angew. Chem. 2017, 129, 6862-6865.
Angew. Chem. Int. Ed. 2017, 56, 6758-6761.
Highlighted in CHEMIE.DE 2017.
Highlighted in Synfacts 2017, 13, 795.
Official press release of the University Leipzig, 14.06.2017, 141/2017.

• M. Schlegel, C. Schneider

"Lewis Acid-Catalyzed Nucleophilic Addition of Indoles to in situ-Generated 2-Amidoallyl Cations"
J. Org. Chem. 2017, 82, 5986-5992.

• S. Schulze, M. Pahl, F. Stolz, J. Appun, B. Abel, C. Schneider, D. Belder

"Liquid beam desorption mass spectrometry for the investigation of continuous flow reactions in microfluidic chips"
Anal. Chem. 2017, 89, 6175-6181.

• T. Hodik, C. Schneider

"Brønsted Acid-Catalyzed, Enantioselective Synthesis of 1,4-Dihydroquinoline-3-Carboxylates via In Situ Generated ortho-Quinone Methide Imines"
Org. Biomol. Chem. 2017, 15, 3706-3716.

• B. Abel, F. Stolz, J. Appun, S. Naumov, C. Schneider

"A complex catalytic reaction caught in the act: Intermediates and products online by liquid µ-beam mass spectrometry and theoretical modeling"
ChemPlusChem. 2017, 81, 233-240.

• C. Weilbeer, M. Sickert, S. Naumov, C. Schneider

"The Brønsted Acid-Catalyzed, Enantioselective Aza-Diels-Alder Reaction for the Direct Synthesis of Chiral Piperidones"
Chem. Eur. J. 2017, 23, 513-518.

• K. Gebauer, C. Schneider

"The First Organocatalytic Cope Rearrangement (Highlight)"
Angew. Chem. 2016, 128, 14416-14417.
Angew. Chem. Int. Ed. 2016, 55, 14208-14209.

• K. Bera, C. Schneider

"Brønsted Acid Catalyzed [3+2]-Cycloaddition of Cyclic Enamides with in Situ Generated 2-Methide-2H-indoles — Enantioselective Synthesis of Indolo[1,2-a]indoles"
Org. Lett. 2016, 18, 5660-5663.

• M. Kretzschmar, T. Hodik, C. Schneider

"Brønsted Acid Catalyzed Addition of Enamides to ortho-Quinone Methide Imines — An Efficient and Highly Enantioselective Synthesis of Chiral Tetrahydroacridines"
Angew. Chem. 2016, 128, 9941-9946.
Angew. Chem. Int. Ed. 2016, 55, 9788-9792.
Highlighted in Synfacts 2016, 12, 970.

• K. Bera, C. Schneider

"Brønsted Acid Catalyzed [3+2]-Cycloaddition of 2-Vinylindoles with In Situ Generated 2-Methide-2H-indoles — Highly Enantioselective Synthesis of Pyrrolo[1,2-a]indoles"
Chem. Eur. J. 2016, 22, 7074-7078.

• S. K. Alamsetti, M. Spanka, C. Schneider

"Synergistic Rhodium/Phosphoric Acid-Catalysis for the Enantioselective Additon of Oxonium Ylides to ortho-Quinone Methides"
Angew. Chem. 2016, 128, 2438-2442.
Angew. Chem. Int. Ed. 2016, 55, 2392-2396.
Highlighted in Synfacts 2016, 12, 376.

• V. A. Nikolaev, J. J. Medvedev, O. S. Galkina, K. V. Azarova, C. Schneider

"Unusual reactions of diazocarbonyl compounds with α,β-unsaturated δ-amino esters: Rh(II)-catalyzed Wolff rearrangement and oxidative cleavage of N–H-insertion products"
Beilstein J. Org. Chem 2016, 12, 1904-1910.

• C. Lindemann, C. Schneider

"Quinolizidine-Based Alkaloids – A General Catalytic, Highly Enantio- and Diastereoselective Synthetic Approach"
Synthesis 2016, 48, 828-844.

• P. R. Nareddy, C. Schneider

"A Highly Enantioselective, Organocatalytic [3+2]-Cycloannulation Reaction towards the de novo-Synthesis of 1-Cyclopentenyl-α-Keto Esters"
Chem. Commun. 2015, 51, 14797-14800.
Comment in "Organocatalyzed C-C Ring Construction" 2016.

• C. Dietze, T. Scholl, S. Ohla, J. Appun, C. Schneider, D. Belder

"Rapid prototyping of microfluidic chips for dead-volume-free MS coupling"
Anal. Bioanal. Chem. 2015, 29, 8735-8743.

• M. Boomhoff, R. Ukis, C. Schneider

"A Highly Stereocontrolled, One-Pot Approach towards Pyrrolobenzoxazinones and Pyrroloquinazolinones through a Lewis Acid-Catalyzed [3+2]-Cycloannulation Process"
J. Org. Chem. 2015, 80, 8236-8244.

• J. J. Medvedev, M. V. Meleshina, T. L. Panikorovskii, C. Schneider, V. A. Nikolaev

"Domino Reactions of Diazodicarbonyl Compounds with α,β-Unsaturated-δ-Amino Esters: Convenient Way Towards 2-Oxopiperidines, Dihydropyridinones, and Isoquinolinediones"
Org. Biomol. Chem. 2015, 13, 9107-9117.

• C. Benz, M. Boomhoff, J. Appun, C. Schneider, D. Belder

"Chip-Based Free-Flow Electrophoresis with Integrated Nanospray Mass-Spectrometry"
Angew. Chem. 2015, 127, 2805–2809.
Angew. Chem. Int. Ed. 2015, 54, 2766–2770.

• S. Saha, C. Schneider

"Directing Group Assisted Nucleophilic Substitution of Propargylic Alcohols via o-Quinone Methide Intermediates: Brønsted Acid Catalyzed, Highly Enantio- and Diastereoselective Synthesis of 7-Alkynyl-12a-acetamido-Substituted Benzoxanthenes"
Org. Lett. 2015, 17, 648–651.

• S. Saha, S. K. Alamsetti, C. Schneider

"Chiral Brønsted Acid-Catalyzed Friedel-Crafts Alkylation of Electron-Rich Arenes with in situ-Generated Ortho-Quinone Methides: Highly Enantioselective Synthesis of Diarylindolylmethanes and Triarylmethanes"
Chem. Commun 2015, 51, 1461–1464.

• S. Saha, C. Schneider

"Brønsted Acid-Catalyzed, Highly Enantioselective Addition of Enamides to in situ-Generated Ortho-Quinone Methides – A Domino Approach Towards the Direct Synthesis of Complex Acetamidotetrahydroxanthenes"
Chem. Eur J. 2015, 21, 2348–2352.

• J. J. Medvedev, O. S. Galkina, A. A. Klinkova, D. S. Giera, L. Hennig, C. Schneider, V. A. Nikolaev

"Domino [4 + 1]-annulation of α,β-unsaturated δ-amino esters with Rh(II)–carbenoids – a new approach towards multi-functionalized N-aryl pyrrolidines"
Org. Biolmol. Chem. 2015, 13, 2640–2651.

• M. Boomhoff, A. K. Yadav, J. Appun, C. Schneider

"Modular, Flexible, and Stereoselective Synthesis of Pyrroloquinolines – Rapid Assembly of Complex Heterocyclic Scaffolds"
Org. Lett. 2014, 16, 6236–6239.

• M. C. Pischl, C. F. Weise, S. Haseloff, M.-A. Müller, A. Pfaltz, C. Schneider

"A Highly Stereoselective and Flexible Strategy for the Convergent Synthesis of Long-Chain Polydeoxypropionates – Application towards the Synthesis of the Glycolipid Membrane Components Hydroxyphthioceranic and Phthioceranic Acid"
Chem. Eur. J. 2014, 20, 17360–17374.

• O. El-Sepelgy, S. Haseloff, S.K. Alamsetti, C. Schneider

"Brønsted Acid-Catalyzed, Conjugate Addition of β-Dicarbonyls to in situ Generated ortho-Quinone Methides – Enantioselective Synthesis of 4 Aryl-4H-Chromenes"
Angew. Chem. 2014, 126, 8057-8061.
Angew. Chem. Int. Ed. 2014, 53, 7923-7927.
Highlighted in Synfacts 2014, 10, 985.

• C. Schneider, F. Abels

"Catalytic, Enantioselective Vinylogous Michael Reactions" (Review)
Org. Biomol. Chem. 2014, 12, 3531-3543.

• F. Abels, C. Lindemann, C. Schneider

"A General Strategy for the Catalytic, Highly Enantio- and Diastereoselective Synthesis of Indolizidine-Based Alkaloids"
Chem. Eur. J. 2014, 20, 1964-1979.

• S. Basu, V. Gupta, J. Nickel, C. Schneider

"Organocatalytic Enantioselective Vinylogous Michael Reaction of Vinylketene Silyl-N,O-Acetals"
Org. Lett. 2014, 16, 274-277.

• C. Schneider, C. Weise

"Cope, Oxy-Cope, and Anionic Oxy-Cope Rearrangements"
Comprehensive Organic Synthesis 2nd Edition (G. Molander, P. Knochel, Eds.), Pergamon Press 2014, Vol. 5, 867-911.

• C. Schneider, M. Boomhoff

"Aldol Reactions in Domino Processes"
Domino Reactions - Concepts for Efficient Organic Synthesis, (L.F. Tietze, Ed.), Wiley-VCH 2014, 267-294.

• M. C. Pischl, C. F. Weise, M.-A. Müller, A. Pfaltz, C. Schneider

"A Convergent and Stereoselective Synthesis of the Glycolipid Components Phthioceranic Acid and Hydroxyphthioceranic Acid"
Angew. Chem. 2013, 125, 9138-9142.
Angew. Chem. Int. Ed. 2013, 52, 8968-8972.

• S. Peruncheralathan, S. Aurich, H. Teller, C. Schneider

"The Ti-BINOLate-Catalyzed, Enantioselective Ring-Opening of meso-Aziridines with Amines"
Org. Biomol. Chem. 2013, 11, 2787-2803.

• V. Gupta, S. Sudhir V., T. Mandal, C. Schneider

"Organocatalytic, Highly Enantioselective, Vinylogous Mukaiyama-Michael Reaction of Acyclic Dienolsilyl Ethers"
Angew. Chem. 2012, 124, 12778-12781.
Angew. Chem. Int. Ed. 2012, 51, 12609-12612.
Highlighted in Synfacts 2013, 9, 95.
Comment: www.organic-chemistry.org/Highlights/2013/08July.shtm

• F. Abels, C. Lindemann, E. Koch, C. Schneider

"A General Organocatalytic Approach toward the Enantioselective Total Synthesis of Indolizidine Based Alkaloids"
Org. Lett. 2012, 14, 5972-5975.
Comment: www.organic-chemistry.org/Highlights/2013/22April.shtm

• M. Boomhoff, C. Schneider

"A Novel 3-Component [3+2]-Cycloannulation Process for the Rapid and Highly Stereoselective Synthesis of Pyrrolobenzoxazoles"
Chem. Eur. J. 2012, 18, 4185-4189.
Highlighted in Synfacts 2012, 8, 606.

• C. F. Weise, M. Pischl, A. Pfaltz, C. Schneider

"A General, Asymmetric, and Non-Iterative Synthesis of Trideoxypropionates. Straightforward Syntheses of the Pheromones (+)-Vittatalactone and (+)-Norvittatalactone"
J. Org. Chem. 2012, 77, 1477-1488.

• A. Marti, S. Peruncheralathan, C. Schneider

„Cationic Late Transition Metal Complexes Catalyze the Ring-Opening of meso-Aziridines with Amines”
Synthesis 2012, 44, 27-36.

• C. F. Weise, F. Richter, S. Immel, C. Schneider

„The Oxy-Cope Rearrangement of Aldol Products - A Combined Experimental and Theoretical Study”
Eur. J. Org. Chem. 2012, 1520-1529.

• S. Ohla, R. Beyreiss, S. Fritzsche, P. Gläser, S. Nagl, K. Stockhausen, C. Schneider, D. Belder

„Monitoring on-Chip Pictet-Spengler Reaction by Integrated Analytical Separation and Label-Free Time-Resolved Fluorescence”
Chem. Eur. J. 2012, 18, 1240-1246.

• F. Abels, C. Schneider

„A Modified and Highly Useful Protocol for the Bronsted Acid-Catalyzed, Enantioselective, Vinylogous Mannich Reaction with Aliphatic Aldimines”
Synthesis 2011, 4050-4058.
Comment: www.organic-chemistry.org/Highlights/2012/30July.shtm

• S. Fritzsche, S. Ohla, P. Gläser, D. S. Giera, M. Sickert, C. Schneider, D. Belder

„Asymmetrische Organokatalyse und Analyse in einem mikrofluidschen Nanospray-Chip”
Angew. Chem. 2011, 123, 9639-9642.
Angew. Chem. Int. Ed. 2011, 50, 9467-9470.
Highlighted in Chem. Unserer Zeit 2011, 45, 370.

• B. M. Ruff, S. Zhong, M. Nieger, M. Sickert, C. Schneider, S. Bräse

„A. Combined Asymmetric Vinylogous Mannich/Diels-Alder Approach for the Stereoselective Synthesis of Highly Functionalized Hexahydroindoles”
Eur. J. Org. Chem. 2011, 6558-6566.

• A. Marti, L. Richter, C. Schneider

„Iron-Catalyzed Ring-Opening of meso-Aziridines with Amines”
Synlett 2011, 2513-2516.
Abstract: www.organic-chemistry.org/abstracts/lit3/426.shtm

• C. F. Weise, M. Pischl, A. Pfaltz, C. Schneider

„A Non-Iterative, Flexible, and Highly Stereoselective Synthesis of Polydeoxypropionates – Synthesis of Vittatalactone”
Chem. Commun. 2011, 47, 3248-3250.

• D. S. Giera, C. Schneider

"InCl3-Catalyzed Allylic Friedel-Crafts Reactions towards the Stereocontrolled Synthesis of 1,2,3,4-Tetrahydroquinolines"
Org. Lett. 2010, 12, 4884.

• H. Schönherr, J. Mollitor, C. Schneider

"A Chemoenzymatic Approach to the Stereocontrolled Synthesis of the C1-C11-Fragment of (+)-Peloruside A"
Eur. J. Org. Chem. 2010, 3908.

• C. Schneider, M. Sickert

"Catalytic, Enantioselective Vinylogous Mannich Reactions in Chiral Amine Synthesis, Methods, Developments and Applications (T. Nugent, Ed.)"
Wiley-VCH, Weinheim 2010, 157.

• M. Sickert, F. Abels, M. Lang, J. Sieler, C. Birkemeyer, C. Schneider

"The Brønsted Acid-Catalyzed, Enantioselective Vinylogous Mannich Reaction"
Chem. Eur. J. 2010, 16, 2806.

• S. Ghosh, M. V. Nandakumar, H. Krautscheid, C. Schneider

"Copper-Bipyridine-Catalyzed Enantioselective a-Amination of ß-Keto Esters"
Tetrahedron Lett. 2010, 51, 1860.

• M. V. Nandakumar, S. Ghosh, C. Schneider

"Enantioselective Synthesis of a Novel Chiral 2,9-Disubstituted 1,10-Phenanthroline and First Applications in Asymmetric Catalysis"
Eur. J. Org. Chem. 2009, 6393.

• C. Enkisch, C. Schneider

"Sequential Mannich-aza-Michael Reaction for the Stereodivergent Synthesis of Highly Substituted Pyrrolidines"
Eur. J. Org. Chem. 2009, 5549.

• D. S. Giera, M. Sickert, C. Schneider

"A Straightforward Synthesis of (-)-Anabasine through the Catalytic, Enantioselective, Vinylogous Mannich Reaction"
Synthesis 2009, 3797.

• S. Peruncheralathan, H. Teller, C.Schneider

"Ti-BINOLat-katalysierte Aminolyse von meso-Aziridinen - ein hochenantioselektiver und direkter Zugang zu 1,2-Diaminen"
Angew. Chem. 2009, 121, 4943.
Angew. Chem. Int. Ed. 2009, 48, 4849.
Highlighted in Synfacts 2009, 873.

• C. Schneider

"Katalytische, enantioselektive Ringöffnungen von Aziridinen"
Angew. Chem. 2009, 121, 2116.
Angew. Chem. Int. Ed. 2009, 48, 2082.

• D. S. Giera, M. Sickert, C. Schneider

"Brønsted Acid-Catalyzed, Enantioselective, Vinylogous Mannich Reaction of Vinylketene Silyl N,O-Acetals"
Org. Lett. 2008, 10, 4259.

• S. Khaliel, M. V. Nandakumar, H. Krautscheid, C. Schneider

"Organocatalytic Domino Mannich Aza-Michael Reactions towards the Stereoselective Synthesis of Highly Substituted Pipecolic Esters"
Synlett 2008, 2705.

• E. Mai, C. Schneider

"Catalytic, enantioselective synthesis of Boc-protected 1,2-amino alcohols through aminolysis of meso-epoxides with benzophenone imine"
Arkivoc 2008, 9, 216.

• M. Sickert, C. Schneider

"Enantioselektive, Brønstedt-Säure-katalysierte, vinyloge Mannich-Reaktion"
Angew. Chem. 2008, 120, 3687.
Angew. Chem. Int. Ed. 2008, 47, 3631.
Highlighted in Synfacts 2008, 756.

• A. Tschöp, M. V. Nandakumar, O. Pavlyuk, C. Schneider

"Scandium-Bipyridine-Catalyzed Selenol Addition to Aromatic meso-Epoxides"
Tetrahedron Lett. 2008, 49, 1030.

• S. Peruncheralathan, M. Henze, C. Schneider

"Indium(III) Chloride-Catalyzed Thiolysis of meso-Aziridines"
Tetrahedron Lett. 2007, 48, 6743.

• S. Peruncheralathan, M. Henze, C. Schneider

"Sc(OTf)3-Catalyzed Aminolysis of meso-Aziridines"
Synlett 2007, 2289.

• E. Mai, C. Schneider

"Indium-Bipyridine-Catalyzed, Enantioselective Aminolysis of meso-Epoxides"
Synlett 2007, 2136.

• M.V.Nandakumar, A. Tschöp, H. Krautscheid, C. Schneider

"Indium-Bipyridine-Catalyzed, Enantioselective Thiolysis of meso-Epoxides"
Chem. Commun. 2007, 2756.
Highlighted in Synfacts 2007, 960.

• F. Jakob, C. Schneider

"Enzyme-Catalyzed Kinetic Resolution of 1,3-Anti-Diol Monoesters. Efficient Preparation of Enantiomerically Highly Enriched and Unsymmetrically Substituted 1,3-Anti-Diols"
Eur. J. Org. Chem. 2007, 2958.

• A. Tschöp, A. Marx, A.R. Sreekanth, C. Schneider

"Scandium-Bipyridine-Catalyzed, Enantioselective Alcoholysis of meso-Epoxides"
Eur. J. Org. Chem. 2007, 2318.

• N. Remme, K. Koschek, C. Schneider

"Scandium-Triflate-Catalyzed Transesterification of Carboxylic Esters"
Synlett 2007, 491.

• E. Mai, C. Schneider

"The Scandium-Bipyridine-Catalyzed, Enantioselective Aminolysis of Meso-Epoxides"
Chem. Eur. J. 2007, 13, 2729.

• C. Schneider

"Synthesis of 1.2-Difunctionalized Fine Chemicals through Catalytic, Enantioselective Ring-Opening Reactions of Epoxides"
Synthesis 2006, 3919.

• C. Schneider, M. Hansch, P. Sreekumar

"Zirconium-BINOLate-catalyzed enantioselective aldol-Tishchenko reactions of aromatic ketone aldols"
Tetrahedron: Asymm. 2006, 17, 2738.

• C. Schneider, S. Khaliel

"Microwave-Assisted Silyloxy-Cope Rearrangements of syn-Aldol Products in DMF: Enhancement of Rate and Diastereoselectivity"
Synlett 2006, 1413.

• C. Schneider

"1,1-Bis(organooxy)alk-1-enes"
Science of Synthesis,  Thieme, Vol. 24.2.6., 2006, 293.

• C. Schneider, M. Hansch

"The Zr(OtBu)₄-Catalyzed Aldol-Tishchenko Reaction of Ketone Aldol Adducts"
Chem. Eur. J. 2005, 11, 3010.

• C. Schneider, K. Klapa, M. Hansch

"Zr(OtBu)₄-Catalyzed Tishchenko Reduction of b-Hydroxy Ketones"
Synlett 2005, 91.

• C. Schneider, A. R. Sreekanth, E. Mai

"Scandium-Bipyridine-Catalyzed, Enantioselective Addition of Alcohols and Amines Towards meso-Epoxides"
Angew. Chem. 2004, 116, 5809-5812; Angew. Chem. Int. Ed. 2004, 43, 5691-5694.

• C. Schneider, M. Hansch

"First Catalytic, Enantioselective Aldol-Tishchenko Reactions with Ketone Aldol Adducts as Enol Equivalents"
Synlett 2003, 837.

• C. Schneider, F. Tolksdorf, M. Rehfeuter

"Asymmetric Synthesis of the Polyol Fragment of the Polyene Macrolide Antibiotic RK-397"
Synlett 2002, 2098.

• C. Schneider

"Katalytische, enantioselektive Synthesen von b-Lactonen - vielseitige Synthesebausteine in der Organischen Chemie (Highlight)" Angew. Chem., 2002, 114, 771; Angew. Chem. Int. Ed. 2002, 41, 744.

• C. Schneider

"Erste de novo-Synthese des Bisindolalkaloids Vinblastin (Highlight)"
Angew. Chem. 2002, 114, 4391; Angew. Chem. Int. Ed. 2002, 41, 4217.

• C. Schneider, O. Reese

"Highly Stereoselective and Efficient Synthesis of Functionalized Cyclohexanes with Multiple Stereocenters"
Chem. Eur. J. 2002, 8, 2585.

• C. Schneider, J. Brauner

"Lewis Base Catalyzed Addition of Trialkylaluminum Compounds to Epoxides"
Eur. J. Org. Chem. 2001, 4445.

• C. Schneider

"The Silyloxy-Cope Rearrangement of Syn-Aldol Products: Evolution of a Powerful Synthetic Strategy"
Synlett 2001, 1079.

• C. Schneider, M. Hansch

"Zr(OtBu)₄-catalysed synthesis of acetone aldol adducts and domino aldol Tishchenko reactions with diacetone alcohol as enol equivalent“
Chem. Comm. 2001, 1218.

• C. Schneider

"Quaternary Ammonium Salt Catalyzed Azidolysis of Epoxides with Trimethylsilyl Azide"
Synlett 2000, 1840.

• C. Schneider, O. Reese

"Diastereoselective Conjugate Additions to tLeucine-Derived N-Enoyl-1,3-oxazolidin-2-ones"
Synthesis 2000, 1689.

• C. Schneider, O. Reese

"Domino-Michael-Aldol- und Domino-Michael-Mannich-Reaktionen. Hochdiastereoselektive Synthese funktionalisierter Cyclohexane"
Angew. Chem. 2000, 112, 3074; Angew. Chem. Int. Ed. 2000, 39, 2948.

C. Schneider, J. Brauner

• "Lewis base catalyzed addition of triethylaluminum to epoxides“

Tetrahedron Lett. 2000, 41, 3043.

• C. Schneider, A. Schuffenhauer

"Stereodivergent Synthesis of Highly Substituted Tetrahydropyrans"
Eur. J. Org. Chem. 2000, 73.

• C. Schneider

"Lewis Acid Reagents (Rezension)"
H. Yamamoto (Hrsg.), Oxford Press, 1999, Angew. Chem. 2000, 112, 834.

• C. Schneider

"New Polyol Syntheses (Book Chapter)"
Organic Synthesis Highlights IV, H.-G. Schmalz (Hrsg.), Wiley-VCH, 2000, 58.

• C. Schneider, M. Rehfeuter

"General and Asymmetric Synthesis of 1,3,5-Triols with Pendant Functional Groups"
Chem. Eur. J. 1999, 5, 2850.

• C. Schneider, C. Börner, A. Schuffenhauer

"Stereoselective Synthesis of Highly Substituted Piperidines"
Eur. J. Org. Chem. 1999, 3353.

• C. Schneider

"Radikale und Radikalionen in der Organischen Synthese (Rezension)"
T. Linker, M. Schmittel, Wiley-VCH, 1998, Nachrichten aus Chemie, Technik und Laboratorium 1999, 47, 1146.

• C. Schneider

"In Memoriam Ulrich Schöllkopf"
Nachrichten aus Chemie, Technik und Laboratorium 1999, 47, 1428.

• C. Schneider

"Application of Transition Metal Catalysts in Organic Synthesis (Rezension)"
L. Brandsma, Springer, 1998, Nachrichten aus Chemie, Technik und Laboratorium 1999, 47, 460.

• C. Schneider

"Die Cope-Umlagerung von Aldolprodukten"
Habilitationsschrift, Göttingen, 1998.

• C. Schneider

"Application of the Silyloxy-Cope Rearrangement of Chiral Aldol Products Towards a Synthesis of (+)-Lasiol"
Eur. J. Org. Chem. 1998, 1661.

• C. Schneider, C. Börner

"Novel and Stereocontrolled Synthesis of Enantiopure and Polyalkylsubstituted Piperidines"
Synlett 1998, 652.

• C. Schneider, M. Rehfeuter

"Enantioselective Polyol Synthesis via the Cope Rearrangement of Chiral Aldol Products. A Synthesis of the C₁-C₁₀-Fragment of Nystatin A₁"
Tetrahedron Lett. 1998, 39, 9.

• C. Schneider

"Neue Polyol-Synthesen"
Angew. Chem. 1998, 110, 1445; Angew. Chem. Int. Ed. 1998, 37, 1375.

• C. Schneider

"Organische Chemie in Goslar ‑ 2. Deutsch-Italien. Symposium (Tagungsbericht)"
Nachrichten aus Chemie, Technik und Laboratorium 1997, 45, 994.

• C. Schneider

"Stereodivergent Synthesis of Enantiopure Tetrahydropyrans via the Silyloxy-Cope Rearrangement of Chiral Aldol Products"
Synlett 1997, 815.

• C. Schneider, M. Rehfeuter

"Highly Stereoselective Cope Rearrangements of Enantiomerically Pure Silylated Syn-Aldols"
Tetrahedron 1997, 53, 133.

• L. F. Tietze, C. Schneider

"Stereodivergent Hetero Diels-Alder Reactions of Chiral 1-Oxa-1,3-butadienes through a Conformational Switch induced by Lewis Acids"
Chem. Eur. J. 1996, 2, 139.

• C. Schneider, M. Rehfeuter

"Stereoselective Cope Rearrangements of Syn- and Anti-Aldol Products"
Synlett 1996, 212.

• L. F. Tietze, C. Schneider

"Ethyl Nitroacetate"
Encyclopedia of Reagents in Organic Synthesis (Hrsg.: L. A. Paquette, S. E. Denmark), Wiley, London, 1995, Vol. 4, 2501.

• L. F. Tietze, C. Schneider

"Diethyl Oxomalonate"
Encyclopedia of Reagents in Organic Synthesis (Hrsg.: L. A. Paquette, S. E. Denmark), Wiley, London, 1995, Vol. 3, 1837.

• L. F. Tietze, A. Montenbruck, C. Schneider

"De Novo Synthesis of Enantiopure Carbohydrates: Preparation of Ethyl b-D- and b-L-Mannopyranosides by an Asymmetrically Induced Hetero Diels-Alder Reaction"
Synlett 1994, 509.

• J. Henkelmann, L. F. Tietze, C. Schneider

"Verfahren zur Herstellung von a,b-ungesättigten g-Oxycarbonsäurehalogeniden",
DE-A14328060, 17.3.94.

• L. F. Tietze, C. Schneider, A. Montenbruck

"Asymmetrically 1,6-Induced Hetero Diels-Alder Reaction of Chiral Oxabutadienes Towards the De Novo Synthesis of Enantiomerically Pure Carbohydrates: Reversal of Diastereofacial Selectivity through Change of Lewis Acid"
Angew. Chem. 1994, 106, 1031; Angew. Chem., Int. Ed. Engl. 1994, 33, 980.

• E. Pohl, R. Herbst-Irmer, M. Noltemeyer, C. Schneider, L. F. Tietze

"The Crystal Structures of endo- and exo-3-Acetoxy-2,4-di-ethoxy-6-(2-oxo-1,3-oxazolidinecarbonyl)-3,4-dihydro-pyran"
Acta Cryst. 1993, C49, 1850.

• L. F. Tietze, C. Schneider, M. Pretor

"Improved Synthesis of (E)-3-Alkoxy- and (E)-3-Phenoxyacryloyl Chlorides"
Synthesis 1993, 1079.

• L. F. Tietze, C. Schneider

"Efficient Control of the Endo/Exo-Selectivity in Intermolecular Hetero Diels-Alder Reactions of a New 1-Oxa-1,3-butadiene with Different Lewis Acids"
Synlett 1992, 755.

• L. F. Tietze, C. Schneider

"Enantioselective Total Synthesis of the Mycotoxin Talaromycin B by a Hetero Diels-Alder Reaction"
J. Org. Chem. 1991, 56, 2476.