Unusual Tridentate N-3 Capping Coordination Behavior of Hexakis(3,5-Dimethylpyrazolyl)cyclotriphosphazene, N3p3(3,5-Me2pz)6 - Synthesis, Spectroscopy, and Electrochemistry of Mononuclear and Dinuclear Copper(ii) Complexes and the X-Ray Structure of N3p3(3

by Thomas, K. R. Justin; Chandrasekhar, Vadapalli; Pal, Parthasarathy; Scott, Syrona Renae Horton; Hallford, Randal L.; Cordes, A. Wallace

The reactions of hexakis(3,5-dimethylpyrazolyl)cyclotriphosphazenc, N3P3(3,5-Me2PZ)6 (HPCTP) (3), with copper(II) halides afford mononuclear HPCTP.CUX2 (X = Cl, 3a; X = Br, 3b) and dinuclear HPCTP.2CuX2 (X = Cl, 3c; X = Br, 3d) coordination complexes. Optical absorption spectra and ESR spectra of these complexes suggest a distorted trigonal bipyramidal geometry around copper in all of the compounds 3a-3d. The structure of HPCTP.CuC12 (3a) was determined by X-ray crystallography. The crystals of 3a are monoclinic, space group P2(1)/n, with a = 21.338 (4) angstrom, b = 11.43 (3) angstrom, c = 18.285 (3) angstrom, beta = 104.37 (2)-degrees, V = 4321(2) angstrom3, and Z = 4. The structure shows that the cyclophosphazene ligand functions as an unprecedented N3 capping ligand: coordination to copper is through two nongeminal pyrazolyl pyridinic nitrogen atoms and one cyclophosphazene ring nitrogen atom, and the geometry around copper is distorted trigonal bipyramidal. Cyclic voltammetric studies have been carried out on complexes 3a-3d.

Journal
Inorganic Chemistry
Volume
32
Issue
5
Year
1993
Start Page
606
ISBN/ISSN
1520-510X; 0020-1669
DOI
10.1021/ic00057a020