Binuclear pentamethylcyclopentadienyl rhodium(III) compounds with pyrazolate and thiolate bridging ligands
Por:
García J.J., Barón G., Arévalo A., Torrens H., Carmona D., Esteban M., Lahoz F.J., López J.A., Oro L.A.
Publicada:
1 ene 1998
Resumen:
Binuclear thiolato-bridged complexes of general formula [(?5-C5Me5)2Rh 2(?-Pz)(?-SR)2]BF4 (Pz=pyrazolate; R=C6F5 (2a), p-C6F4H (2b), p-C6H4F (2c) or C6H5 (2d)) have been prepared by reacting the hydroxo-pyrazolato-bridged compound [(?5-C5Me5)2Rh 2(?-Pz)2(?-OH)] BF4 with the corresponding thiol. Complexes 2a-d show two types of fluxionality: rotation around the thiol C-S bond and isomerization among the three possible isomers in which the thiols occupy axial and/or equatorial positions within the Rh2S2 metallacycle. These processes are studied by 1H and 19F NMR spectroscopies. The crystal structures of 2b and 2d were established by X-ray crystallography. Compound 2b crystallises in the monoclinic space group P21/n, with lattice parameters a=14.368(2), b=18.252(2), c=15.268(2) Å, ?=109.79(1)° and Z=4. Complex 2d crystallises in a monoclinic lattice, space group C2/c, with a=48.723(5), b=8.7503(8), c=40.334(4) Å, ?=112.620(5)° and Z=16. Both cationic dinuclear complexes exhibit very similar molecular structures with analogous pseudo-octahedral environments for the rhodium centres. Each metal is bonded to a terminal ?5-C5Me5 group and to three bridging ligands: two monodentate thiolates (p-SC6F4H in 2b and SC6H5 in 2d) and a bidentate pyrazolate group. The main structural dissimilarity affects the relative configuration of the thiolate phenyl substituents giving rise to syn (2b) or anti (2d) structures.
Filiaciones:
García J.J.:
Depto. de Quim. Inorgánica, Fac. Quim., Univ. Nac. Auton. Mex., 04510 México, D.F., Mexico
Barón G.:
Depto. de Quim. Inorgánica, Fac. Quim., Univ. Nac. Auton. Mex., 04510 México, D.F., Mexico
Arévalo A.:
Depto. de Quim. Inorgánica, Fac. Quim., Univ. Nac. Auton. Mex., 04510 México, D.F., Mexico
Torrens H.:
Depto. de Quim. Inorgánica, Fac. Quim., Univ. Nac. Auton. Mex., 04510 México, D.F., Mexico
Carmona D.:
Depto. de Quim. Inorgánica, Inst. Cie. Mat. Aragon, Univ. Z., 50009 Zaragoza, Spain
Esteban M.:
Depto. de Quim. Inorgánica, Inst. Cie. Mat. Aragon, Univ. Z., 50009 Zaragoza, Spain
Lahoz F.J.:
Depto. de Quim. Inorgánica, Inst. Cie. Mat. Aragon, Univ. Z., 50009 Zaragoza, Spain
López J.A.:
Depto. de Quim. Inorgánica, Inst. Cie. Mat. Aragon, Univ. Z., 50009 Zaragoza, Spain
Oro L.A.:
Depto. de Quim. Inorgánica, Inst. Cie. Mat. Aragon, Univ. Z., 50009 Zaragoza, Spain
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