Copper-Catalyzed Regioselective Allylic Cyanation of Allylic Compounds with Trimethylsilyl Cyanide

Abstract

The copper-catalyzed regioselective allylic cyanation of allylic compounds with trimethylsilyl cyanide (TMSCN) is described. Copper(I) iodide (CuI), copper(I) cyanide (CuCN) and copper(II) chloride (CuCl₂) are shown to effectively catalyze the cyanation of various allylic substrates to afford the corresponding allylic cyanides in good yields and high regioselectivities. The reaction in the presence of 2,2,6,6-tetramethyl-1-piperidinyloxy free radical (TEMPO) reveals that the cyanation proceeds via a radical pathway.