Aquation, Solvolysis, and Anation

Substitution at platinum(ii) may be involved when Pt complexes are used to catalyse substitution at platinum(iv). Some new views on the role of the platinum(ii) species in such reactions have been offered. The notion of direct relevance to this chapter is that the primary step is formation of a dinuclear intermediate directly from the simple hydrated platinum(ii) complex and the platinum(iv) complex. Aquation, Solvolysis, and Anation. The kinetics of aquation of [PtClJ over the range 50—70 °C are consistent with data published earlier for aquation at lower 

Albinati, A. Musco, G. Carturan, and G. Strukul, Inorg. Chim. Acta, 1976, 18, 219. F. Pesa and M. Orchin,/. Organometallic Chem., 1976, 108, 135. 

Aquation of /ra j-[PtBr(gly)(NH3)] is catalysed by Hgaq. The mechanism is of an equilibrium formation of a Pt—Br—Hg intermediate, followed by slow generation of the /ranj-[Pt(gly)(NH3)(OHa)]+ product. The enthalpy and entropy of formation of the bromo-bridged dinuclear intermediate, its u.v.-visible spectrum, and its kinetics of decomposition, have been measured.  

---