Asymmetric Synthesis of 1,4‐Dicarbonyl Compounds from Aldehydes by Hydrogen Atom Transfer Photocatalysis and Chiral Lewis Acid Catalysis

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(47), P. 16859 - 16863

Published: Sept. 20, 2019

Abstract Enantioenriched 1,4‐dicarbonyl compounds are versatile synthons in natural product and pharmaceutical drug synthesis. We herein report a mild pathway for the efficient enantioselective synthesis of these directly from aldehydes through synergistic cooperation between neutral eosin Y hydrogen atom transfer photocatalyst chiral rhodium Lewis acid catalyst. This method is distinguished by its operational simplicity, abundant feedstocks, economy, ability to generate products high yields (up 99 %) enantioselectivity % ee ).

Language: Английский

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Synthesis of Enantioenriched Vicinal Tertiary and Quaternary Carbon Stereogenic Centers within an Acyclic Chain

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(1), P. 36 - 49

Published: May 13, 2019

Abstract Overcoming the inherent difficulty to prepare quaternary carbon stereogenic centers, diastereo‐ and enantioselective preparation of acyclic backbones possessing vicinal tertiary centers (i.e. in a 1,2‐relationship) causes distorted geometries represents very acute problem organic synthesis. Several approaches are discussed this minireview underlining challenges illustrated by rather limited number available practitioners.

Language: Английский

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Stereodivergent Synthesis of Enantioenriched 2,3-Disubstituted Dihydrobenzofurans via a One-Pot C–H Functionalization/Oxa-Michael Addition Cascade

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(23), P. 8583 - 8589

Published: June 1, 2021

A one-pot rhodium-catalyzed C–H functionalization/organocatalyzed oxa-Michael addition cascade reaction has been developed. This methodology enables the stereodivergent synthesis of diverse 2,3-disubstituted dihydrobenzofurans with broad functional group compatibility in good yields high levels stereoselectivity under exceptionally mild conditions. The full complement stereoisomers chiral and 3,4-disubstituted isochromans could be accessed at will by appropriate permutations two catalysts. current work provides a rare example catalysts independently controlling contiguous stereogenic centers subsequently via two-step single operation.

Language: Английский

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Synthetic exploration of sulfinyl radicals using sulfinyl sulfones

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: Sept. 2, 2021

Sulfinyl radicals - one of the fundamental classes S-centered have eluded synthetic application in organic chemistry for over 60 years, despite their potential to assemble valuable sulfoxide compounds. Here we report successful generation and use sulfinyl a dual radical addition/radical coupling with unsaturated hydrocarbons, where readily-accessed sulfones serve as precursor. The strategy provides an entry variety previously inaccessible linear cyclic disulfurized adducts single step, demonstrates tolerance extensive range hydrocarbons functional groups. Experimental theoretical mechanistic investigations suggest that these reactions proceed through sequential sulfonyl addition.

Language: Английский

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Diastereodivergent Aldol‐Type Coupling of Alkoxyallenes with Pentafluorophenyl Esters Enabled by Synergistic Palladium/Chiral Lewis Base Catalysis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(33)

Published: June 17, 2022

As a fundamental and synthetically useful C-C bond formation reaction, the aldol reaction is one of most versatile transformations in organic synthesis. However, despite extensive research on asymmetric versions unified method for stereoselective access to complementary syn anti diastereomeric products remains be developed. In this study, we developed synergistic palladium/chiral Lewis base system that overcomes inherent diastereoselectivity bias reactions and, as result, allowed us achieve first diastereodivergent coupling alkoxyallenes with pentafluorophenol esters. Computational studies suggest mechanism involving an intermolecular protonative hydropalladation pathway rather than palladium-hydride migratory insertion pathway. The origin stereochemistry catalysis rationalized by DFT calculations.

Language: Английский

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