METAL-COMPLEXES CONTAINING INORGANIC (CARBON-FREE) CHELATE RINGS - REACTIVITY OF THE [RE=O]3+ CORE TOWARD BIS(DIPHENYL-PHOSPHINO)AMINE DERIVATIVES - CRYSTAL-STRUCTURES OF [REOCL2(N(XPPH2)2)(PPH3)] (X = O OR S) AND [REO(OET)-(N(SPPH2)2)2]

The complexes [ReOCl3(PPh3)2] and [ReOCl2(OEt)(PPh3)2] react with an excess of NH(OPPh2)2 to give [ReOCl2{N(OPPh2)2}(PPh3)] 1. When the donor atoms are changed by using NH(SPPh2)2 as the ligand the mono- and di-substituted complexes [ReOCl2{N(SPPh2)2}(PPh3)] 2 and [ReOCl-{N(SPPh2)2}2] 3a are obtained. Complex 3a can also be prepared by using the anionic compound [ReOCl4]- as the starting material. When complex 3a is crystallized from CH2Cl2-EtOH, [ReO(OEt){N(SPPh2)2}2] 3b is obtained. The structures of complexes 1, 2 and 3b were determined by X-ray crystallography. Compound 1 is triclinic, space group P1BAR, with a = 14.885(5), b = 13.815(5), c = 10.019(5) angstrom, alpha = 92.35(3), beta = 108.46(3), gamma = 99.10(3)-degrees and Z = 2. The structure was refined to R = 0.028, based on 4204 observed reflections. Compound (2) is triclinic, space group P1BAR, with a = 16.831(5), b = 14.667(5), c = 9.918(5) angstrom, alpha = 99.48(3), beta = 104.93(3), gamma = 92.57(3)-degrees and Z = 2. The structure was refined to R = 0.038, based on 5955 observed reflections. Compound 3b is trinclinic, space group P1BAR, with a = 10.214(5), b = 10.750(5), c = 13.947(4) angstrom, alpha = 111.72(3), beta = 113.07(3), gamma = 64.06(3)-degrees and Z = 1. The structure was refined to R = 0.063, based on 4062 observed reflections. All three compounds show slightly distorted octahedral geometries. The chlorine atoms are trans in 1 and cis in 2. The Re-O(oxide) bonds show some triple bond character, and exert a strong trans influence.