Platinum(II) and palladium(II) complexes of tetrakis(pyrazolyl)cyclotriphosphazenes

Reactions of tetrakis(pyrazolyl)cyclotriphosphazene derivatives, gem-N3-P3Ph2Pz4 (2) and gem-N3P3Ph2(dmpz)4 (4), with PdCl2(PhCN)2 or PtCl2(PhCN)2 afforded complexes of the type MCl2L (L = 2 or 4). The detailed spectroscopic (proton, 13C and 31P NMR) investigations revealed that in these complexes the phosphazenes act as bidentate N2-donor ligands via the two geminal pyrazolyl pyridinic nitrogen atoms, thus forming six-membered chelate rings. The platinum derivative N3P3Ph2Pz4 · PtCl2 (6) reacted further with CuCl2 to yield a new heterobimetallic derivative, N3P3Ph2Pz4·PtCl 2·CuCl2 (9). The EPR spectra of 9 indicated a distorted five-coordinate geometry around copper. The electrochemistry of 9 is also reported. Copyright © 1997 Elsevier Science Ltd.