207689-52-9Relevant academic research and scientific papers
Binuclear pentamethylcyclopentadienyl rhodium(III) compounds with pyrazolate and thiolate bridging ligands
Garcia, Juventino J.,Baron, Gerardo,Arevalo, Alma,Torrens, Hugo,Carmona, Daniel,Esteban, Montserrat,Lahoz, Fernando J.,Lopez, Jose A.,Oro, Luis A.
, p. 55 - 65 (2007/10/03)
Binuclear thiolato-bridged complexes of general formula [(η5-C5Me5)2Rh 2(μ-Pz)(μ-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 [(η5-C5Me5)2Rh 2(μ-Pz)2(μ-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) A, β=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) A, β=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 η5-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.
