Pd Nanoparticle-Catalyzed Stereospecific Mizoroki–Heck Arylation of cis-1,2-Disilylarylethylenes

Abstract

In the presence of catalytic amounts of Pd nanoparticles, generated from Pd 2 dba 3 /Ag(I), cis-1,2-ditrimethylsilylarylethylenes undergo with aryl iodides a stereospecific Mizoroki−Heck arylation leading to trans-ditrimethylsilyldiarylethylenes. This chemoselectivity is in contrast to that of their trimethylgermyl analogues, which are arylated at the position of the C−Ge bonds. trans-1,2-Ditrimethylsilylarylethylenes are completely unreactive under the standard reaction conditions. The reaction tolerates the presence of boryl, silyl, or bromine substituents on the aryl iodides. From a mechanistic point of view, the process involves syn-arylpalladation followed by syndehydropalladation.