Diastereoselective synthesis of spiro[cyclopropane-1,3′-indolin]-2′-ones through metal-free cyclopropanation using tosylhydrazone salts

Abstract

Anticancer spiro[cyclopropane-1,3′-indolin]-2′-ones are accessible through a transition metal-free diastereoselective cyclopropanation using <italic>in situ</italic> generated diazo-compounds.