aDepartment of Chemistry, University of California, Santa Barbara, CA 93106, USA
bDepartment of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
Abstract:
The ‘heterogenized’ water gas shift catalyst Rh/P4VP, prepared from the reaction of RhCl3 with poly(4-vinylpyridine), is also active for hydrogenation and hydroformylation of 1-hexene and cyclohexene in aqueous ethoxyethanol under mild shift reaction conditions (typically 0.9 atm. PCO at 100°C). The catalytic activities for these systems were studied as functions of several experimental variables. Hydroformylation rates increased with the PCO but exhibited saturation behavior in the 1.5 atm. range. Rates for cyclohexane and hexane production were inhibited by CO at higher pressures. Cyclohexene hydroformylation and hydrogenation turnover frequencies were independent of the polymer-loading (50–150 μM RhCl3/1.0 g P4VP) indicating that the active species are of the same nuclearity as the principal species present. The temperature dependence did not follow simple Arrhenius behavior, but appeared segmented. These data are discussed in terms of possible mechanisms.