A Highly Stereoselective Synthesis of α-Carbethoxy-α,β-unsaturated Phosphonates Mediated by Tri-n-Butylarsine
摘要:
A highly stereoselective synthesis of alpha-carbethoxy-alpha,beta-unsaturated phosphonates in 71-92% yield mediated by tri-n-butylarsine under neutral condition is described.
A Catalytic Michael/Horner-Wadsworth-Emmons Cascade Reaction for Enantioselective Synthesis of Thiochromenes
作者:Abhijnan Ray Choudhury、Santanu Mukherjee
DOI:10.1002/adsc.201300281
日期:2013.7.8
A catalyticenantioselective sulfa‐Michael/Horner–Wadsworth–Emmonsreactioncascade has been developed, taking advantage of phosphonate as an electrophilic activator and a traceless binding site. Using a chiral bifunctional urea derivative as the catalyst, a variety of aryl and heteroaryl substituted thiochromenes was obtained in excellent yield with a high level of enantioselectivity.