835628-61-0Relevant articles and documents
Chemistry of metal-metal-bonded early-late heterobimetallics: Cooperative reactions of functional groups at a persistent organometallic Zr-Rh framework
Cornelissen, Carsten,Erker, Gerhard,Kehr, Gerald,Froehlich, Roland
, p. 214 - 225 (2005)
The reaction of (C5H4-PPh2) 2Zr(CH3)2 (5a) with HRh(COXPPh 3)3 (6) leads to methane evolution and the formation of the early-late heterobimetallic complex [(μ-C5H 4-PPh2)2-(H2C-Zr-Rh(CO)PPh 3)] (7a), which was characterized by X-ray diffraction (d(Zr-Rh) = 2.863(1) A). The analogous dialkylphosphino-substituted complexes (C 5H4-PR2)2Zr(CH2) 2 (5b, R = isopropyl; 5c, R = cyclohexyl) react with the hydrido-rhodium reagent 6 to initially form the analogous bimetallic (Zr-Rh) complexes 7b,c, respectively. However, these complexes are not stable at ambient temperature in toluene solution, due to an equilibration with the products [(μ-C5H4-PR2)2(μ-CH 3-Zr-Rh(PPh3))] (11) and [(μ-C5H 4-PR2)2(H3C-Zr-Rh-(CO)2)] (10). Treatment of the initially formed complexes 7b,c with carbon monoxide rapidly leads to the formation of the H3C(Zr-Rh)-dicarbonyl complexes 10b,c. The product 10bc was characterized by X-ray crystal structure analysis. The systems 7b,c are not stable in dichloromethane. They react readily with the solvent by abstraction of two chlorine atoms to yield the compounds [(μ-C5H4-PR2)2(μ-0=C(CH 3))(Cl-Zr-Rh-Cl)] (12b,c). Both products were characterized by X-ray diffraction. A cooperative action of the involved metals is assumed to account for the observed reactions at the intact heterobimetallic Zr-Rh framework.
