Direct Catalytic Asymmetric Vinylogous Additions of α,β‐ and β,γ‐Butenolides to Polyfluorinated Alkynyl Ketimines
作者:Barry M. Trost、Chao‐I. (Joey) Hung、Manuel J. Scharf
DOI:10.1002/anie.201806249
日期:2018.8.27
We report a Zn‐ProPhenol catalyzed asymmetric Mannich reaction between butenolides and polyfluorinated alkynyl ketimines to obtain vinylogous products featuring two contiguous tetrasubstituted stereogenic centers. Notably, this is the first successful use of ketimines in the ProPhenol Mannich process, and the reaction offers a new approach for the preparation of pharmaceutically relevant products possessing
A directvinylogousMichael reaction of gamma-substituted deconjugated butenolides with nitroolefins has been developed with the help of a newly identified quinine-derived bifunctional catalyst, allowing the synthesis of densely functionalized products with contiguous quaternary and tertiary stereocenters in excellent yield with perfect diastereoselectivity (>20:1 dr) and high enantioselectivity (up
Catalytic asymmetric formal γ-allylation of deconjugated butenolides
作者:Amit K. Simlandy、Santanu Mukherjee
DOI:10.1039/c5ob02362a
日期:——
A formal γ-allylation of deconjugatedbutenolides is reported based on a two-step sequence consisting of a catalytic diastereo- and enantioselective vinylogous nucleophilic addition to vinyl sulfones and Julia–Kocienski olefination. This highly modular approach delivers densely functionalized butenolides containing a quaternarystereogenic centre in excellent yield with high enantioselectivity.
The present invention provides a compound having the structure:
本发明提供了一种具有以下结构的化合物:
Synergistic Lewis base and anion-binding catalysis for the enantioselective vinylogous addition of deconjugated butenolides to allenoates
作者:Vikas Kumar、Santanu Mukherjee
DOI:10.1039/c3cc46858e
日期:——
An enantioselective vinylogous umpolung addition of deconjugated butenolides to allenoates has been developed for the first time with the help of synergistic combination of an achiral phosphine and a chiral squaramide, and represents the first example of a catalytic enantioselective Cγ–Cγ bond formation between two different carbonyl partners.