Palladium(II)-catalyzed tandem annulation reaction of o-alkynylbenzoates with methyl vinyl ketone for the synthesis of isocoumarins
作者:Huan Wang、Xiuling Han、Xiyan Lu
DOI:10.1016/j.tet.2013.07.057
日期:2013.10
A palladium(II)-catalyzed highly regioselective tandem reactions of o-alkynylbenzoates with methyl vinyl ketone for the synthesis of isocoumarins was developed. It is a convenient, mild and environmentally benign reaction with moderate to high yield. The reaction is initiated by the Pd(II) species and regenerate the Pd(II) species to complete the catalytic cycle without the necessity of a redox system
Highly regioselective nucleopalladation for the oxidative coupling of internal alkynes with alkenyl alcohols by using green and low-costing oxygen as the sole oxidant was investigated. This one-pot cascade cyclization proceeds through Pd-catalyzed intramolecular C–O bond cyclization, insertion of nonbiased alkenyl alcohols, β-H elimination, and reinsertion of a HPdX species, which is finally transferred