Metallation of Tris(1-pyrazolyl)methane by Dimethylplatinum(II)

Tris(l-pyrazolyl)methane (HCpz3) reacts with Pt(CH3)2(COD) to form Pt(CH3)2(HCpz3), and when this complex is heated in pyridine metallation of the pyrazole ring at C(5) occurs to form Pt(CH3)(HCpz2(pzH-1))(py). A triphenylphosphine derivative, Pt(CH3)(HCpz2(PzH-1)(PPh3)2, when slowly heated to 185°C forms Pt(HCpz2(pzH-1))(C6H4PPh2); this complex has both the nitrogen and phosphorus donor ligands metallated to form six and four membered rings, respectively.