Mechanistic Insights into C(sp(2))-C(sp)N Reductive Elimination from Gold(III) Cyanide Complexes

摘要

A new family of phosphine-ligated dicyanoaryl-gold(III) complexes has been prepared and their reactivity towards reductive elimination has been studied in detail. Both, a highly positive entropy of activation and a primary C-12/13 KIE suggest a late concerted transition state while Hammett analysis and DFT calculations indicate that the process is asynchronous. As a result, a distinct mechanism involving an asynchronous concerted reductive elimination for the overall C(sp(2))-C(sp)N bond forming reaction is characterized herein, for the first time, complementing previous studies reported for C(sp(3))-C(sp(3)), C(sp(2))-C(sp(2)), and C(sp(3))-C(sp(2)) bond formation processes taking place on gold(III) species.