Highly Enantioselective Iridium-Catalyzed Hydrogenation of Conjugated Trisubstituted Enones
作者:Bram B. C. Peters、Jira Jongcharoenkamol、Suppachai Krajangsri、Pher G. Andersson
DOI:10.1021/acs.orglett.0c04012
日期:2021.1.1
Asymmetric hydrogenation of conjugated enones is one of the most efficient and straightforward methods to prepare optically active ketones. In this study, chiral bidentate Ir–N,P complexes were utilized to access these scaffolds for ketones bearing the stereogenic center at both the α- and β-positions. Excellent enantiomeric excesses, of up to 99%, were obtained, accompanied with good to high isolated
Chemoselective Luche-Type Reduction of α,β-Unsaturated Ketones by Magnesium Catalysis
作者:Yoon Kyung Jang、Marc Magre、Magnus Rueping
DOI:10.1021/acs.orglett.9b03131
日期:2019.10.18
The chemoselective reduction of α,β-unsaturatedketones by use of an economic and readily available Mg catalyst has been developed. Excellent yields for a wide range of ketones have been achieved under mild reaction conditions, short times, and low catalyst loadings (0.2-0.5 mol %).
Asymmetric catalysis with readily available, cheap, and non-toxic alkaline earth metal catalysts represents a sustainable alternative to conventional synthesis methodologies. In this context, we describe the development of a first MgII -catalyzed enantioselective hydroboration providing the products with excellent yields and enantioselectivities. NMR spectroscopy studies and DFT calculations provide
Stereodivergent Evolution of Artificial Enzymes for the Michael Reaction
作者:Xavier Garrabou、Duncan Stuart Macdonald、Basile I. M. Wicky、Donald Hilvert
DOI:10.1002/anie.201712554
日期:2018.5.4
Enzymes are valuable biocatalysts for asymmetric synthesis due to their exacting stereocontrol. Changing the selectivity of an existing catalyst for new applications is, however, challenging. Here we show that, in contrast, the stereoselectivity of an artificialenzyme created by design and directed evolution is readily tunable. We engineered a promiscuous artificial retro‐aldolase into four stereocomplementary
Copper-catalysed enantioselective stereodivergent synthesis of amino alcohols
作者:Shi-Liang Shi、Zackary L. Wong、Stephen L. Buchwald
DOI:10.1038/nature17191
日期:2016.4.21
process to prepare and fully characterize all possible stereoisomers of a drug candidate for biological evaluation. Despite many advances in asymmetric synthesis, developing general and practical strategies for obtaining all possible stereoisomers of an organic compound that has multiple contiguous stereocentres remains a challenge. Here, we report a stereodivergent copper-based approach for the expeditious