Synthesis, reactivity and X-ray crystal structures of mixed thiazolato- or carboxylato-carbonyl(phosphine)-rhenium(I) complexes

The compound [Re(CO)3(PPh3)2Cl] reacts with the lithium salt of thiazole derivatives (L1H = 2-amino-benzothiazole, L2H = 2-N-methyl-aminothiazole, L3H = 2-N-phenylaminothiazole, L4H = 2-N-(4-methoxyphenyl)aminothiazole, L5H = 2-N(4-nitrophenyl)aminothiazole) to give [Re(CO)2-(PPh3)2(L)]. The compounds have been characterized by elemental analysis, i.r. and1H n.m.r. spectra. At room temperature [Re(CO)2(PPh3)(L2)] reacts with L6H (L6H = diphenylacetic acid), to give the carboxylato complex [Re(CO)2[Figure not available: see fulltext.]. The crystal structures of [Re(CO)2(PPh3)2(L2)] (2) and [Re(CO)2(PPh3)2(L6)] (6) were determined by x-ray crystallography. [Re(CO)2(PPh3)2(L2)] crystallizes in the monoclinic space group P21/m with a = 9.16(1), b= 24.82(2), c =9.12(1) Å, and β = 115.81(4)°; Dc = 1.56 g cm-3for Z = 2. The structure was refined to a final R of 6.4%. The molecules have Cs symmetry. The rhenium atom is six-coordinate with approximately octahedral geometry. The anionic ligand is chelating through the nitrogen atoms and is strictly planar allowing delocalization of the π-electron density. [Re(CO)2(PPh3)2(L6)] (6) crystallizes in the monoclinic space group P21/n with a = 22.203(5), b = 18.651(5), c =10.653(3) Å, β = 91.08(3)°, Dc = 1.47 g cm-3 for Z = 4. The structure was refined to a final R of 4.7%. The complex is monomeric and the rhenium atom is distorted octahedral with two mutually trans PPh3 ligands, two cis CO ligands and one chelating Ph2CHCO2- ion. © 1985 VCH Verlagsgesellschaft mbH.

The mixed thiazolato- or carboxylato-carbonyl(phosphine)-rhenium(I) complexes are synthesized and characterized. The crystal structure is also achieved.