Syntheses of Isochromenes and Naphthalenes by Electrophilic Cyclization of Acetylenic Arenecarboxaldehydes

摘要

Highly substituted 1H-isochromenes,isobenzofurans,and pyranopyridines can be prepared by allowing o-(1-alkynyl)arenecarboxaldehydes and ketones to react with I_2,ICl,NIS,Br_2,NBS,p-O_2NC_6H_4SCl,or PhSeBr and various alcohols or carbon-based nucleophiles at room temperature.Naphthyl ketones and iodides are also readily prepared by the reaction of 2-(1-alkynyl)arenecarboxaldehydes with I_2 and simple olefins or alkynes.