Asymmetric Synthesis of Dihydronaphthoquinones Containing Adjacent Stereocenters via a Sulfa-Michael Addition Triggered Ring-Expansion Approach
摘要:
A novel asymmetric synthetic approach for the construction of enantioenriched functionalized dihydroquinones incorporating adjacent quaternary and tertiary stereocenters has been reported, in which enantioenriched 3-allylic phthalides engaged in an unprecedented sulfa-Michael addition-triggered Stereoselective ring-expansion reaction, and furnished the desired sulfur-incoporated dihydronaphthoquinones with high stereoselectivity.
Asymmetric Synthesis of Functionalized Dihydronaphthoquinones Containing Quaternary Carbon Centers via a Metal-Free Catalytic Intramolecular Acylcyanation of Activated Alkenes
作者:Zhe Zhuang、Zhi-Peng Hu、Wei-Wei Liao
DOI:10.1021/ol501427h
日期:2014.6.20
metal-free catalytic annulation was developed through a Lewis base-catalyzed asymmetric allylic alkylation and the ensuing unprecedented asymmetric intramolecular acylcyanation of alkenes. This protocol provides a unique and facile access to prepare enantioenriched densely functionalized dihydronaphthoquinones accompanied by enantiomerically pure 3,3-disubstituted phthalides bearing quaternarycarbon centers