| Thermoregulated phase-transfer catalysis (TRPTC) provides not only a realistic possibility for the hydroformylation of higher olefins in aqueous/organic baphasic system but also a promising avenue for the recycling of noble metal catalysts. In this paper,a kind of nonionic phosphine ligands with the characteristics of cloud point was synthesized and the structure of these ligands have been characterized through NMR technique, of which the structure is shown below:In addition, rhodium complexes formed in situ between RhCl3·3H2O and above mentioned two ligands have been used in hydroformylation of mixed C11-12 olefins in aqueous/organic biphasic system, respectively. The effects of different reaction conditions have been investigated and discussed in detail. Under the optimized conditions, the conversion of mixed C11-12 olefins and the yield of aldehyde reached up to 90%.The catalysts can be recycled 4 times without evident loss in activity.The average leaching of rhodium into the product phase has been detected by ICP-AES.From the result we can see that the leaching of rhodium in the product phase can be reduced by increasing the cloud point of the phosphine ligands.
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