Regioselective Hydrogenolysis of Donor–Acceptor Cyclopropanes with Zn-AcOH Reductive System

A convenient
low-cost method for regioselective ring-opening of
donor–acceptor cyclopropanes with the Zn-AcOH reductive system
was developed. The general character of the method was displayed via
efficient reduction of a representative series of 2-(het)­arylcyclopropane-1,1-diesters
as well as donor–acceptor cyclopropanes with other types of
electron-withdrawing activating groups. This method opens a rapid
access to γ-substituted propyl-1,1-diesters, ketoesters, cyanoesters,
cyanoamides, dinitriles, etc., many of which are not readily accessible
with alternative methods. The utility of the synthesized compounds
was demonstrated by transforming them into valuable acyclic and cyclic
compounds (including pharmacologically relevant carbazoles, δ-lactams,
and oxindole derivatives).