Highly regio- and stereoselective synthesis of indene derivatives via electrophilic cyclization

Indene or naphthalene derivatives are readily prepared in moderate to excellent yields with high regio- and stereoselectivity under very mild reaction conditions by the reaction of acetylenic malonates and ketones with I-2, ICI, or NIS. The resulting iodides can be further elaborated using palladium-catalyzed coupling reactions.