Rhodium(III)-catalyzed directed peri-C-H alkenylation of anthracene derivatives.

Abstract

Rhodium(III)-catalyzed oxidative coupling reactions of anthracene-9-carboxylic acid derivatives with electron-deficient olefins are reported. A cationic rhodium(III) catalyst, in combination with a copper(II) oxidant, promotes selective monoalkenylation of anthracene-9-carboxamide, affording 1-alkenylanthracene-9-carboxamide in moderate to good yields. A similar catalytic system also promotes the reaction of anthracene-9-carboxylic acid and an electron-deficient olefin, which affords a lactone derivative through C-H alkenylation followed by intramolecular conjugate addition.