Dendrimer Load Transition Metal Catalyst Preparation And Recycling, 1 - Hexene Hydroformylation Reaction

Although the catalytic activity of homogeneous catalysts is higher, but the catalyst and organic small molecules of reactant and product separation and catalyst recycling recycling is still a major factor restricting the application of homogeneous catalysts. Conventional separation methods such as distillation, extraction can not be applied to some special effects, for example, the product of a higher boiling point, and the deactivation of the catalyst in the extraction process of regeneration. Easier to recycle and reuse of the heterogeneous catalyst, but limited contact by the contact area due to the catalyst and reactants, the catalytic efficiency and catalytic activity is restricted. Based on this, we designed and fabricated to the dendrimer as a carrier, catalyst loading of small molecules to the dendrimers on the formation of homogeneous catalytic system, dendritic supported catalysts by ion exchange. And catalyst for the hydroformylation reaction of olefins. Details are as follows:Containing phosphoric acid groups or sulfonic acid groups of the two phenyl xanthene phosphine ligand was prepared from9,9-dimethyl-xanthene, synthesis and structure of the product by NMR and IR characterization results show that, contain phosphate groups, two phenyl xanthene phosphine ligand is more difficult synthesis of diphenyl xanthene phosphine ligands containing sulfonic acid groups were successfully synthesized.Dendritic polyglycerol as raw material, one-pot1,2-dimethyl imidazole,6-bromhexine chloride prepared by the reaction end groups containing cationic dendrimers. Synthesis containing sodium diphenyl xanthene phosphine ligands and rhodium complexes with dendrimers of small molecules by ion-exchange load in the formation of the dendrimer polymer load phosphine rhodium catalyst. And diphenyl the xanthene phosphine ligand bonded to the polymer on the conditions were optimized, the results show that the ligand and the number of polymer mole ratio of1:2ligand bonded to the polymer the best results.Will prepared dendrimers load the phosphine rhodium catalysts for the reaction of1-hexene homogeneous catalytic hydroformylation, ultrafiltration recovery study of recovery and recycling of the catalyst on the catalytic activity and selectivity. The results showed that the dendrimer load phosphine rhodium catalyst with small molecule catalyst compared to the1-hexene hydroformylation reaction, the catalytic activity of dendritic load high, but low selectivity. Dendritic polymer supported phosphine rhodium catalyst after four times recycling loop catalytic experiments, the lower the catalytic activity of1-hexene little, but its catalytic selectivity greater reductions.