N-benzylation/benzylic C-H amidation cascade by the (ζ3- Benzyl)palladium system in aqueous media: An effective pathway for the direct construction of 3-phenyl-3,4-dihydro-(2H)-1,2,4-benzothiadiazine 1,1-dioxides

Abstract

We demonstrate a unique strategy for a benzylation/benzylic C-H amidation cascade reaction by the (ζ3-benzyl)palladium system derived from a palladium catalyst and benzyl alcohol. This tandem process is devised as a new synthetic route for 3-phenyl-3,4-dihydro-(2H)-1,2,4-benzothiadiazine-1,1- dioxide. Water plays an important role for the smooth generation of the (ζ3-benzyl)palladium species, and a bis-benzylated Pd(II) intermediate would be formed in our catalytic system. Atom economical processes such as benzylic C-H activation, cascade reactions and chemoselective reactions in aqueous media have been developed. © 2013 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim.