Radical‐Polar Crossover Annulation: A Platform for Accessing Polycyclic Cyclopropanes
作者:John A. Milligan、Kevin L. Burns、Anthony V. Le、Viktor C. Polites、Zheng‐Jun Wang、Gary A. Molander、Christopher B. Kelly
DOI:10.1002/adsc.201901051
日期:2020.1.7
to the cyclopropanation of olefins that are embedded within bicyclic scaffolds. Whereas these systems are notoriously recalcitrant toward classical cyclopropanation approaches, RPC cyclopropanation can be executed with ease, leading to polycarbocyclic and polyheterocyclic cyclopropanes. The cyclopropanation proceeds through a photoredox‐enabled Giese‐type radical addition followed by an intramolecular
Enantioselective Alkylation of β-Keto Esters by Phase-Transfer Catalysis Using Chiral Quaternary Ammonium Salts
作者:Eun Joo Park、Mi Hee Kim、Dae Young Kim
DOI:10.1021/jo0401772
日期:2004.10.1
Catalytic enantioselectivealkylationpromoted by a quaternary ammonium salt from cinchonine as a phase transfer catalyst is described. Treatment of cyclo β-ketoesters with alkyl halide under mild reaction conditions afforded the corresponding α-alkylated β-ketoesters in moderate to excellent yields with high enantiomeric excesses
Chatterjee, Amareshwar; Dutta, Lakshmi N.; Chatterjee, Swapan K., Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1980, vol. 19, # 11, p. 955 - 960
作者:Chatterjee, Amareshwar、Dutta, Lakshmi N.、Chatterjee, Swapan K.
DOI:——
日期:——
Organocatalytic Enantioselective Protonation of Silyl Enolates Mediated by Cinchona Alkaloids and a Latent Source of HF