Synthesis and characterization of sterically hindered thiolate Pd(II) complexes of the type [Pd(SR) 2(TMEDA)]: Examination of their catalytic properties in phosphane-free Suzuki-Miyaura cross couplings

Abstract

The sterically hindered thiolate complexes [Pd(SR) 2(TMEDA)] SR = SC 6F 5 ( 2), SC 6F 4-4-H ( 3), SC 6H 4-2-SiPh 3 ( 4) were easily synthesized by metathetical reactions of the corresponding palladium chloro compound [Pd(Cl) 2(TMEDA)] ( 1) and the lead salt of the corresponding thiol. The identity of the three species being unequivocally determined by single crystal X-ray diffraction techniques. The catalytic activity of the palladium species [Pd(SR) 2(TMEDA)] was explored in the Suzuki–Miyaura cross coupling reactions of different p-substituted bromobenzenes.