Enantioselective Ammonium Ylide Mediated One‐Pot Synthesis of Highly Substituted γ‐Butyrolactones

T Drennhaus, L Öhler, S Djalali… - Advanced Synthesis …, 2020 - Wiley Online Library
T Drennhaus, L Öhler, S Djalali, S Höfmann, C Müller, J Pietruszka, D Worgull
Advanced Synthesis & Catalysis, 2020Wiley Online Library
An ammonium ylide mediated access towards trans‐β, γ‐disubstituted, all‐trans‐α, β, γ‐
trisubstituted, and α, α, β, γ‐tetrasubstituted γ‐butyrolactones bearing a broad variety of
functionalities was developed. Starting from widely accessible benzylidene Meldrum's acid
derivatives and α‐bromo carbonyl compounds, γ‐butyrolactones were obtained in yields
between 32–99% with up to excellent diastereoselectivities (> 95: 5) via a DABCO‐mediated
[2+ 1] annulation. Utilization of enantiomerically pure cinchona alkaloid derivatives enables …
Abstract
An ammonium ylide mediated access towards trans‐β,γ‐disubstituted, all‐transα,β,γ‐trisubstituted, and α,α,β,γ‐tetrasubstituted γ‐butyrolactones bearing a broad variety of functionalities was developed. Starting from widely accessible benzylidene Meldrum's acid derivatives and α‐bromo carbonyl compounds, γ‐butyrolactones were obtained in yields between 32–99% with up to excellent diastereoselectivities (>95:5) via a DABCO‐mediated [2+1] annulation. Utilization of enantiomerically pure cinchona alkaloid derivatives enables the first asymmetric ammonium ylide mediated method to provide (3R, 4R)‐β,γ‐disubstituted and (2R, 3R, 4R)‐α,β,γ‐trisubstituted γ‐butyrolactones in moderate to good yields with up to very good enantiomeric ratios (97:3). The scalability of the transformation was proven while determining the absolute configuration.
Wiley Online Library
以上显示的是最相近的搜索结果。 查看全部搜索结果