An inexpensive and efficient Pd(OAc)2/tetramethylguanidine
(TMG) or PdCl2/TMG catalytic system has been developed for the Heck
reaction of an olefin with an aryl halide. The TONs were up to 1000000 when
iodobenzene was used as the substrate with butyl acrylate as the reactant. In
addition, [Pd(TMG)4]Cl2(H2O)8, an
air-stable compound, effectively promoted the Heck reaction, which demonstrated
that TMG acted as a ligand in this reaction system.
