Cobalt-catalyzed carbocyclization of o-iodobenzaldehydes and o-iodophenylketones with alkynes

Org Lett. 2003 Oct 16;5(21):3963-6. doi: 10.1021/ol035514s.

Abstract

[reaction: see text] Treatment of various o-iodobenzaldehydes and o-iodophenyl ketones with alkynes in the presence of Co(dppe)I(2) and Zn powder in acetonitrile at 80 degrees C afforded the corresponding indenols in moderate to excellent yields with exceedingly high regioselectivity. For most unsymmetrical alkynes tested, the carbocyclization gave a single regioisomer.