Masayoshi Nakahara

Trans-influence of a coordinating nitrosyl group: preparation and structure of cis-trihalogeno(8-quinolinolato or its derivative)nitrosylruthenate(1−)

Abstract Hydrous nitrosylruthenium(III) halide reacts with 8-quinolinol or its derivative (2-methyl- or 5-chloro-8-quinolinol) in ethyl alcohol or acetonitrile to give [RuX3(N-O)(NO)]− [X = Cl or Br; H(N-O) = 8-quinolinol or its derivative]. All the halide ions are coordinated cis to the nitrosyl and the 8-quinolinolato oxygen trans to the nitrosyl, as found from an X-ray crystallographic study. The structure of the complex anion reflects a strong π-acceptor ability of the nitrosyl. The compounds obtained were also examined by 13C NMR and negative-SIMS (secondary-ion mass spectrometry).

Preparation and characterisation of bis(1,1,1,5,5,5-hexafluoropentane-2,4-dionato)copper(II) complexes with diazaaromatic compounds. Part 1. Crystal structures and characterisation of several adducts with diazines

The reactions of [Cu(hfac)2](Hhfac = 1,1,1,5,5,5-hexafluoropentane-2,4-dione) with diazines (tmpyz = 2,3,5-trimethylpyrazine, mpym = 5-methylpyrimidine and mpydz = 3-methylpyridazine) in light petroleum have been studied and the following complexes obtained: [{Cu(hfac)2}3(µ-tmpyz)2]1b, [Cu(hfac)2(tmpyz)]1e, [{Cu(hfac)2(µ-mpym)n}]2a, [{Cu(hfac)2}3(µ-mpym)2]2b, [{Cu(hfac)2}2(µ-mpym)]2c, [Cu(hfac)2(mpym)2]2d, and [Cu(hfac)2(mpydz)2]3d. The crystal structures of 1b, 2b and 3d have been determined. Although 1b and 2b are both trinuclear complexes with bridging diazole molecules, the geometry around atom Cu(2) is trigonal bipyramidal for 1b and tetragonal pyramidal for 2b. The geometry around atom Cu(1) is tetragonal bipyramidal in both complexes. The distance Cu(1)–N(1) is longer in 1b than in 2b, while the Cu(2)–N(2) is somewhat shorter in the former. The steric effects of the ligands on the structural differences between these complexes are discussed. On the basis of the relation between the geometry of the co-ordinated hfac ligands and ν(C–O) values, structures of some of the other complexes are suggested.