| One key challenge in the commercial development of homogeneous catalysis has always been the separation of precious metal catalyst from the product. In the past decades ever-increasingly efforts to immobilize catalyst on polymeric or inorganic supports and heterogenise the catalyst and product into separate and immiscible phases have been taken in the direction to tackle this problem, and exciting achievements have been obtained. A novel concept of Thermoregulated Phase-Transfer Catalysis (TRPTC) recently proposed by our research group was just one of the exciting advancement in this areaOn the basis of TRPTC principle, a novel nonionic water-soluble phosphite derived by polyalkylene glycol (OPGPP) was synthesized in the paper. Introduction of certain length of polyoxyethylene moities to the phosphites bestows them with a function of inverse temperature-dependent water solubility and the phosphites gave clear cloud points.The cloud points of the phosphites are dependent on the hydrophile to hydrophobe ratio of the molecule. Addition of certain inorganic salt to aqueous phosphite solution will decrease cloud points of the solution.From the curve of addition quantity of inorganic salt via the cloud points, some cloud points above 100癈 can be deduced.The aqueous phase hydrogenation of allyl alcohol under atmospheric pressure is designed in order to investigate the role of the cloud point in catalytic reactivities.Because of the inverse temperature-dependent water solubility of polyether-substituted water-soluble ligands, an interesting anti-Arrhenius kinetic behavior has been observed. When the reaction system is heated to a temperature above the cloud point nonionic water-soluble phosphine modified rhodium catalyst will precipitate from the aqueous phase ,which drastically reduces the reaction rate of hydrogenation.Such a result suggests that the cloud point property of polyether-substituted nonionic water-soluble phosphines has a remarkable effect on the catalytic behaviors of their transition metal complexes.According to the principle of TRPTC, Rh complexes modified with polyalkyl glycol ether derived phosphine could precipitate from the aqueous phase at a temperature higherthan Cp of the phosphine and then transfer into organic phase to catalyze the reaction. After the reaction, the complexes return to the aqueous phase and separated by simple phase separation at a temperature below Cp and could be employed in the successive reaction runs. The above OPGPP modified rhodium was applied in the aqueous biphasic hydroformylation of higher alpha-olefins. On the conditions of Sub/Rh=1000,P/Rh=13,80癈,5.0Mpa,the reaction could be completed in 3 hours.The conversions of various olefins are higher above 95% with yields of aldehyde of above 95% and ratios of normal aldehyde to iso-aldehyde 0.6 to 2.0.Catalyst can be easily separated from the product but the catalytic activity of the catalyst decreased sharply in the fourth reaction run. When ratio of P/Rh increased to 50, catalyst recycling was improved markedly.31P-NMR was employed to analyze the aqueous OPGPP solution after keeping for 72 hours at 80癈 and completely hydrolysis was proved .Hence decrease of the catalytic activity of the above catlyst was mainly probably due to the hydrolysis of the P-O-C bond of the phosphite in the presence of water.Farther study the property of OPGPP was done in the paper .It was found that OPGPP could dissolve in some hot organic solvents but it precipitated from the solution when cooling to room temperature.ICP technique was applied to determine the solubility of OPGPP in the solvent at different temperature. The results indicated a very low solubility of OPGPP in some alkanes at a low temperature. When OPGPP/Rh complex was applied to catalyse the hydroformylation of 1-Decene in absence of water, the reaction could be finished in 4 hours on the optimal conditions:Sub/Rh=1000,P/Rh=13,90 癈 ,5.0Mpa .Conversion of olefin and yield of aldehyde are higher above 95% with a ratio of normal aldehyde to iso-aldehyde of 0.94.T...
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