Oxidative Cross-Coupling of <i>N</i>-(2‘-Phenylphenyl)benzene- sulfonamides or Benzoic and Naphthoic Acids with Alkenes Using a Palladium−Copper Catalyst System under Air

Abstract

N-(2‘-Phenylphenyl)benzenesulfonamides react with acrylate esters accompanied via cleavage of the C−H bond at their 2‘-position in the presence of a catalyst system of Pd(OAc)2 and Cu(OAc)2 and a base under air to produce 5,6-dihydro-5-(benzenesulfonyl)phenanthridine-6-acetate derivatives in high yields. The reactions of benzoic acid with butyl acrylate and styrene can also give 3-[(butoxycarbonyl)methyl]phthalide and 3-phenylisocoumarin, respectively.