THE INVESTIGATION OF CARBONYLATION REACTIONS UTILIZING POLYMER MODIFIED TRANSITION METAL COMPLEXES.

摘要

Carbonylation reactions, hydroformylation and carabomethoxylation, were investigated using transition metal complexes preanchored to a polymeric resin.; The hydroformylation studies involved an infrared (IR) investigation of (RhH(CO)(PPh(,3))(,3)) bound to phosphinated gel-form polystyrene-divinylbenzene beads. The spectra were recorded at ambient temperature and at 18 atmospheres total pressure. In situ IR techniques were developed and used in this study to determine the effect of reactant partial pressure on the composition of the bound complex. Hydrogen and carbon monoxide saturation partial pressure were varied. The resulting spectra were interpreted by comparing them with the published homogeneous spectra. Two dominant species were observed at 0.67 CO/H(,2), a bis(phosphine)dicarbonyl complex and a dimer. The relative amounts of each were affected by the CO/H(,2) ratio. An absorbance band characteristic of aldehyde was used to establish hydroformylation activity.; Carbomethoxylation studies were conducted to characterize Pd bound to two different ion exhange resins: Amberlyst 15, a macroreticular sulfonated polstyrene resin, and a perfluorinated ion exchange polymer, Nafion. A batch reactor was used to measure the rates and selectivity at 100 C and 800 psig CO pressure. XPS, IR and STEM techniques were used to characterize the catalyst system further. A model was proposed which explains the results of the experiments for both Amberlyst-Pd and Nafion-Pd catalysts. The main feature of the model utilizes the observed phenomenon that soluble species formed during the reaction. This was proven by using a heterogeneous catalyst, Pd/SiO(,2), with a heterogeneous Amberlyst 15 acid resin. The results revealed that Nafion was intrinsically more effective than Amberlyst 15 at activating Pd. The findings also suggest that using heterogeneous acid cocatalysts with homogeneous complexes may be a viable commercial alternative.