Ethylene Carbonylation in Methanol and in Aqueous Media by Palladium(II) Catalysts Modified with 1,1‘-Bis(dialkylphosphino)ferrocenes
摘要:
Palladium(II) complexes with the formula [Pd(H2O)(OTs)(P-P)]OTs, where P-P is 1,1'-bis-(dimethylphosphino)ferrocene (dmpf), 1,1'-bis(diethylphosphino)ferrocene (depf), or 1,1'-bis-(diisopropylphosphino)ferrocene (dippf), have been synthesized and used to catalyze the carbonylation of ethylene in MeOH, water, or a 1/1 water/1,4-dioxane mixture. In MeOH, the reactions catalyzed by the dmpf and depf complexes gave alternating polyketone (alt-E-CO), while methyl propanoate and 3-pentanone were selectively produced with the dippf catalyst. The last catalyst was inactive in aqueous solvent. In contrast, the dmpf and depf catalysts were active in either water or water/1,4-dioxane for the copolymerization of CO with ethylene. These two catalysts were efficient also for the terpolymerization of CO with ethylene and propene in MeOH or water/1,4-dioxane. Operando high-pressure NMR experiments and in situ reactions with model compounds have provided useful information to rationalize the activity and selectivity of the catalytic systems investigated.
Ethylene Carbonylation in Methanol and in Aqueous Media by Palladium(II) Catalysts Modified with 1,1‘-Bis(dialkylphosphino)ferrocenes
摘要:
Palladium(II) complexes with the formula [Pd(H2O)(OTs)(P-P)]OTs, where P-P is 1,1'-bis-(dimethylphosphino)ferrocene (dmpf), 1,1'-bis(diethylphosphino)ferrocene (depf), or 1,1'-bis-(diisopropylphosphino)ferrocene (dippf), have been synthesized and used to catalyze the carbonylation of ethylene in MeOH, water, or a 1/1 water/1,4-dioxane mixture. In MeOH, the reactions catalyzed by the dmpf and depf complexes gave alternating polyketone (alt-E-CO), while methyl propanoate and 3-pentanone were selectively produced with the dippf catalyst. The last catalyst was inactive in aqueous solvent. In contrast, the dmpf and depf catalysts were active in either water or water/1,4-dioxane for the copolymerization of CO with ethylene. These two catalysts were efficient also for the terpolymerization of CO with ethylene and propene in MeOH or water/1,4-dioxane. Operando high-pressure NMR experiments and in situ reactions with model compounds have provided useful information to rationalize the activity and selectivity of the catalytic systems investigated.