Study On Hydrogenation Of Rosin And α-Pinene With Thermoregulated Transfer Catlysts

The active center of catalysts in hydrogenation of rosin andα-pinene were Pd or Ni, at present. However, they have problem of expensive Pd was easy to run off and catalytic activity of Ni was not high. In order to solve those problems thermoregu-lated transfer catalysts were used in hydrogenation of rosin andα-pinene.In this paper four kinds of thermoregulated phosphine ligands: fatty alcohol polyoxyethylene ether 1,2-phenylene phosphate ester (FAPEPP), methoxy polyEth-ylene glycol diphenylphosphine(MGPPE), tri-methoxy polyEthylene glycol phosphine(TMPGP), and fatty alcohol polyoxyethylene ether diphenyl phosphate ester (TAPEPP), were prepared and characterized by FT-IR and 1HNMR. Then the cloud point of this four kinds of ligands were mensurated by extrapolation, the result were 103℃, 112℃, 107℃and 106℃,show that all the prepared phosphine ligands have thermoregulated function.The prepared thermoregulated phosphine ligands were respectively reaction with palladium chloride by in-situ synthesis, obtained four kinds of thermoregulated transfer catalysts (Pd/FAPEPP, Pd/MGPPE, Pd/TMPGP and Pd/TAPEPP). These catalysts were used in the hydrogenation of rosin, the Pd/FAPEPP show excellent catalytic activity. Under optimum reaction conditions, the percent of abietic acid could be under 1 %, the percent of dehydroabietic acid 5.6 %. This result conforms to the national standards. The regeneration of catalyst was investigated. After cycling five times, without any transaction to catalyst, the percent of abietic acid could be under 1 %, the percent of dehydroabietic acid 8.3 %, the catalyst still have high ac-tivity.On the basis of the above research, the FAPEPP was respectively reaction with rhodium chloride, ruthenium chloride and cobalt chloride by in-situ synthesis, ob-tained three kinds of thermoregulated transfer catalysts (Rh/FAPEPP, Ru/FAPEPP and Co/FAPEPP). These catalysts were used in the hydrogenation of rosin, the Ru/FAPEPP show better catalytic activity. Under optimum reaction conditions, the percent of abietic acid could be under1 %, the percent of dehydroabietic acid 3.6%. The regeneration of catalyst was investigated. After cycling five times, the percent of abietic acid could be under2.1 %, the percent of dehydroabietic acid 7.0%, the cata-lyst still have high activity too.During used Pd/FAPEPP in catalytic hydrogenation ofα-pinene, we discovered the Conversion ofα-pinene 100 %, cis-pinene yield 53.8%, show that isomerization ofα-pinene has take place during the process of reaction. The reason is that some acid materials in phosphine ligand can catalyse the isomerization ofα-pinene. Con-tinue studying find that palladium chloride has better catalytic activity in oil/aqueous biphase. So the reaction conditions were investigated. Under optimum reaction con-ditions the yield of cis-pinane abietic acid could be over 99.7 %. After cycling three times, the yield of cis-pinane abietic acid could be 99.5 %, the catalyst still has high activity.Through above-mentioned study, thermoregulated transfer catalysts were suc-cessfully appied to hydrogenation of rosin, palladium chloride have been showed high catalytic activity in oil/aqueous biphase hydrogenation ofα-pinene. Based on all the study in this paper catalyst in hydrogenation of rosin andα-pinene will be ex-tended in the future.