An Efficient and Remarkably Regioselective Synthesis of Benzocyclobutenones from Benzynes and 1,1-Dimethoxyethylene

Article abstract of DOI:10.1021/jo00133a031

New efficient methodology for the synthesis of substituted benzocyclobutenones is presented that involves the <2+2> cycloaddition of various substituted benzynes to 1,1-dimethoxyethylene followed by hydrolysis to the corresponding ketone.In most cases studied a high degree of regioselectivity was observed.These observations are consistent with a nonsynchronous mechanism wherein steric and inductive considerations can be used to account for the products observed.