Broad-Scope Amination of Aryl Sulfamates Catalyzed by a Palladium Phosphine Complex

Abstract

Among phenol-derived electrophiles, aryl sulfamates are attractive substrates since they can be employed as directing groups for C–H functionalization prior to catalysis. However, their use in C–N coupling is limited only to Ni catalysis. Here, we describe a Pd-based catalyst with a broad scope for the amination of aryl sulfamates. We show that the N-methyl-2-aminobiphenyl palladacycle supported by the PCyp2ArXyl2 ligand (Cyp = cyclopentyl; ArXyl2 = 2,6-bis(2,6-dimethylphenyl)phenyl) efficiently catalyzes the C–N coupling of aryl sulfamates with a variety of nitrogen nucleophiles, including anilines, primary and secondary alkyl amines, heteroaryl amines, N-heterocycles, and primary amides. DFT calculations support that the oxidative addition of the aryl sulfamate is the rate-determining step. The C–N coupling takes place through a cationic pathway in the polar protic medium.