Inhibition of reductive elimination of diorganopalladium species by formation of tetraorganopalladates
Abstract
Reductive elimination of (tBuCC)2Pd(PPh3)2 to give tBuC
CC
CBut(4) is strongly inhibited by an excess of LiC
CBut through the formation of Li2Pd(C
CBut)4, which does not readily decompose to produce (4); these results provide, for the first time, a mechanistic interpretation of the hitherto puzzling inhibitory action of highly electropositive metals, such as Li, in Pd-promoted coupling reactions.