SYNTHESIS AND SPECTROSCOPIC STUDIES OF RUTHENIUM COMPLEXES WITH POLY(PYRAZOL-1-YL)METHANE LIGANDS - CRYSTAL-STRUCTURE OF [RUCL(COD)(TPZM)]CL.ETOH [COD = CYCLOOCTA-1,5-DIENE, TPZM = TRIS(PYRAZOL-1-YL)METHANE]

Neutral six-co-ordinate complexes of Ru(II), [RuCl2(bpzm)(cod)] 1 and [RuCl2(btpzm)(cod)] 2 with bis(pyrazol-1 -yl)methane (bpzm) or bis(5-trimethylsilylpyrazol-1 -yl)methane (btpzm) were synthesised from [{RuCl2(cod)}n] (cod = cycloocta-1,5-diene) and the corresponding ligand. Complex 1 reacts with LiBEt3H to give the hydride [RuH(Cl)(bpzm)(cod)] 3. The reactivity of 2 allowed the synthesis of the new complex [RuCl2(btpzm)2].0.5thf 4 (thf = tetrahydrofuran) with two bidentate btpzm ligands. The reaction of [{RuCl2(cod))n] with the tris(pyrazol-1 -yl)methane ligand (tpzm) yielded the six-co-ordinate cationic complex [RuCl(cod)(tpzm)]Cl.EtOH 5. Finally, the reaction of [RuCl3(tpzm)] with both pyridine and triethylamine afforded [RuCl2(py) (tpzm) ] 6. Spectroscopic data are provided for all these compounds. The crystal structure of compound 5 has been determined by X-ray diffraction methods: monoclinic, space group P2(1)/c, with a = 9.330(2), b = 15.579(4), c = 15.667(4) angstrom, beta = 97.79(2)-degrees and Z = 4. The structure has been solved from diffractometer data by direct and Fourier methods and refined by full-matrix least squares to R = 0.0414 for 3362 observed reflections. It consists of complex cations, chloride anions and ethanol molecules of solvation linked by strong hydrogen bonds. The ruthenium is approximately octahedrally co-ordinated to one tridentate tpzm ligand, one chioride ion and two eta2-C=C olefinic groups of the cod ligand.