The Pd(0) complexes generated from Pd0(dba)2 and PhSCH2CH2SPh are more reactive in oxidative additions with aryl halides than those generated from Pd0(dba)2 and Ph2PCH2CH2PPh2.
The kinetics of the oxidative addition of bidentateligand-chelated Pd0 complexes to phenyl iodide and bromidehas been studied via cyclic voltammetry. The dibenzylideneacetone (dba) delivered by the palladium precursor Pd(dba)2 wasfound to affect the concentration of the more reactive dba-freePd0 complex and consequently the kinetics of the overalloxidative addition. The complexes generated from Pd(dba)2 andPhSCH2CH2SPh (pte) were found to be considerably morereactive than those generated from Pd(dba)2 and Ph2PCH2CH2PPh2 (dppe). The former complexes can react with PhBr at lowtemperatures.