Delineating the critical role of acid additives in Mn-catalysed C–H bond functionalisation processes

Abstract

Addition of co-catalytic Cy₂NH to Mn-catalysed C–H bond activation reactions suggests that the conjugate acid, Cy₂NH₂X, influences catalysis. Here, acids are shown to positively influence C–H bond alkenylation catalysis involving alkynes. For certain types of alkynes an acid additive is critical to catalysis. In stark contrast, acids retard catalysis involving acrylates. [Cy₂NH₂]X salts also play a key role in thwarting catalyst degradation to manganese clusters. Our findings enable unreactive substrates to be alkenylated.