First palladium- and nickel-catalyzed oxidative diamination of alkenes: Cyclic urea, sulfamide, and guanidine building blocks

摘要

We recently reported the first catalytic diamination of alkenes. This protocol calls for the use of Pd(II) as catalyst in combination with PhI(OAc)2 as terminal oxidant and furnishes the final diamines as cyclic ureas. It consists of an unprecedented two-step reaction of aminopalladation and C_(sp3)-N-bond formation involving a Pd(IV) species. Introduction of Ni(II) catalysts for homogeneous oxidation allows for an efficient diamination with sulf-amides, which lead to convenient liberation of the free diamines. In related protocols, the substrate scope of the diamination has been broadened to the formation of cyclic guanidines.