Solvent effects on the rate of oxidative addition of methyl iodide to di(4-thiocresol)(2,2′-bipyridyl) platinum(II)

The reaction of methyl iodide with di(4-thiocresol)(2,2′-bipyridyl) platinum(II) to give iodo (methyl) di(4-thiocresol)(2,2′-bipyridyl) platinum(IV) follows the rate law, rate=K2[Pt-(4-thiocresol)2 (2,2′-bipyridyl)] [MeI]. The values of K2 increase with increasing polarity of the solvent, suggesting a polar transition state for the reaction.