Reactions of Rh(PNP) pincer complexes with terminal alkynes: Homocoupling through a ring or not at all

Abstract

Through use of a bespoke macrocyclic variant, we demonstrate a novel approach for tuning the reactivity of rhodium PNP pincer complexes that enables formation of conjugated enynes from terminal alkynes, rather than vinylidene derivates. This concept is illustrated using tert-butylacetylene as the substrate and rationalised by a ring-induced switch in mechanism.