Intramolecular Cooperative C-C Bond Cleavage Reaction of 1,3-Dicarbonyl Compounds with 2-Iodoanilines to Give o-(N-Acylamino)aryl Ketones and Multisubstituted Indoles.

A copper-catalyzed C-C bond cleavage reaction of 1,3-dicarbonyl compounds with 2-iodoanilines was developed. In this process, the ortho effect played an important role in the reactivity and a new reaction pathway that involved a (2-aminophenyl)-bis-(1,3-dicarbonyl) copper species was clearly observed by a time-course HRMS analysis of the reaction mixture. Unlike the previous reports, both the nucleophilic and electrophilic parts of the 1,3-dicarbonyl compound were coupled with 2-iodoaniline by C-C bond cleavage to form o-(N-acylamino)aryl ketones, which could be efficiently converted into multisubstituted indoles.