894084-13-0Relevant academic research and scientific papers
Displacement of phenyl and styryl ligands by benzophenone imine and 2-vinylpyridine on ruthenium and osmium
Bull, Maria L.,Esteruelas, Miguel A.,Goni, Eva,Olivan, Montserrat,Onate, Enrique
, p. 3076 - 3083 (2008/10/09)
The phenyl complexes MPhCl(CO)(PiPr3)2 (M = Ru (3), Os (4)) have been prepared by reaction of MHCl(CO)(P iPr3)2 (M = Ru (1), Os (2)) with HgPh 2. In solution the phenyl ligand of these compounds rotates around the M-Ph bond. The activation parameters for the process are ΔH? = 13.0 ± 0.6 kcal·mol-1 and ΔS? = 1.5 ± 1.3 cal·mol-1·K-1 for 3 and ΔH? = 11.7 ± 0.5 kcal·mol-1 and ΔS? = -5.4 ± 1.2 cal·mol-1·K -1 for 4. The addition of benzophenone imine to dichloromethane solutions of 3 and 4 and the related styryl complexes M{(E)-CH=CHPh}Cl(CO) (PiPr3)2 (M = Ru (7), Os (8)) leads to equilibrium mixtures between the starting compounds and the six-coordinate derivatives MPhCl(NH=CPh2)(CO)(PiPr3) 2 (M = Ru (5): ΔHo = -8.6 ± 0.4 kcal·mol-1, ΔSo = -42.5 ± 1.6 cal·mol-1·K-1; M = Os (6): ΔH o = -9.1 ± 0.8 kcal·mol-1, ΔS o = -31.0 ± 2.6 cal·mol-1·K -1) and M{(E)-CH=CHPh}Cl(NH= CPh2)(CO)(P iPr3)2 (M = Ru (9): ΔHo = -9.5 ± 0.3 kcal·mol-1, ΔSo = -39.4 ± 1.1 cal·mol-1·K-1; M = Os (10): ΔHo = -8.8 ± 0.8 kcal·mol-1, ΔSo = -27.3 ± 2.6 cal·mol -1·K-1). In toluene under reflux complexes 3, 4, 7, and 8 react with benzophenone imine and 2-vinylpyridine to afford the metalated derivatives M{C6H4C(Ph)=NH}Cl(CO)PiPr 3)2 (M = Ru (11), Os (12)) and M(NC5H 4-o-CH=CH)Cl-(CO)(PiPr3)2 (M = Ru (13), Os (14)), releasing benzene and styrene. Complexes 9, 12, and 13 have been characterized by X-ray diffraction analysis. The structure of 9 shows a Cl...H-N hydrogen bond (2.47 A) between the NH hydrogen atom of the imine and the chloride ligand.
