【作者】 吴丹；

【导师】 蒋景阳；

【作者基本信息】 大连理工大学 ， 应用化学， 2013， 博士

【摘要】 高碳醇是一种重要的化工原料,高碳烯烃氢甲酰化法是生产高碳醇的主要方法之一。目前,高碳烯烃氢甲酰化主要采用均相的羰基钴或膦改性羰基钴为催化剂,存在钻催化剂分离和回收困难的问题。因此,开发易分离且可循环使用的钴催化剂具有重要的意义。水-有机两相催化体系以廉价无毒的水为反应介质,是重要的均相催化多相化方法。但多数有机底物不溶于水或水溶性差,导致反应速率缓慢。本课题组金子林等基于温控配体浊点的特性,提出了“温控相转移催化”的概念,为从根本上解决了水-有机两相催化体系的应用范围受底物水溶性限制的问题开创了一条新途径。温控相转移催化已成功用于铑配合物催化的水-有机两相高碳烯烃氢甲酰化反应,但尚未用于钴配合物催化水-有机两相的相关反应。本论文将温控相转移催化拓展至钴配合物催化的水-有机两相高碳烯烃的氢甲酰化反应,以温控相转移钴配合物为催化剂,考察其在水-有机两相高碳烯烃氢甲酰化反应中的催化性能及循环使用情况。根据均相钴膦配合物催化剂中膦配体的特点,本论文合成了含有聚乙氧基链的温控膦配体L1,并基于L1设计合成了两个新的温控膦配体L2和L3(结构见图2.1)。采用原位合成的方法制备了温控相转移钴配合物催化剂(分别记作Co2(CO)8/L、Co2(CO)8/L2和Co2(CO)8/L3)。分别考察了三个温控相转移钴配合物催化1-辛烯氢甲酰化反应的催化性能,不同反应条件的影响及催化剂的循环使用性能。实验结果表明,采用温控相转移钴配合物催化剂的水-有机两相体系可获得与采用钻膦配合物催化剂的均相体系相近的催化活性和选择性,壬醛和壬醇收率可达93%,产物直链率可达85%,氢甲酰化反应没有受到底物1-辛烯水溶性差的限制。反应结束后,含有温控相转移钴配合物催化剂的水相可不经处理直接用于循环反应,经过5次循环使用,催化剂总的TON可达365。本论文还考察了CO2(CO)8/L,和Co2(CO)8/L2催化C11-12混合烯烃的催化性能。实验结果表明,由于催化剂具有异构化活性,均可得到以直链C12-13醛和醇为主的产物,直链率可达69%,C12-13醛和醇的收率可达86%。经过5次循环使用,催化剂总的TON可达187。本论文探索了由廉价钻化合物与温控膦配体直接生成温控相转移钻配合物催化剂。研究发现,醋酸钴或乙酰丙酮钴在氢甲酰化条件下与温控膦配体L1生成的钴配合物催化剂与Co2(CO)8/L1催化性能相当。初步证实了醋酸钴和乙酰丙酮钴与温控膦配体L1在氢甲酰化反应条件下均可形成与Co2(CO)8为前体时相同的羰基钴膦配合物。更多还原

【Abstract】 Higher alcohols are important industrial chemicals. Hydroformylation of higher olefins is one of the main routes to produce higher alcohols. At present, homogeneous cobalt carbonyl or its phosphine complex is used as the catalyst in the hydroformylation plants of higher olefins, even though the difficult separation and recovery of the cobalt catalyst is still a problem. So it is of great importance to develop a cobalt catalyst which can be easily separated and recycled.Aqueous-organic biphasic catalysis with cheap nontoxic water as the reaction medium is a method for the heterogenization of homogeneous catalysis. But the insolubility or poor solubility of most organic substrates results in rather low reaction rate. Base on the cloud point of thermoregulated ligands, a concept of the thermoregulated phase-transfer catalysis (TRPTC) has been developed by Jin and co-workers. The TRPTC has been successfully applied in the aqueous-organic biphasic hydroformylation of higher olefins catalyzed by the rhodium complexes. But so far no publication has been referred to the cobalt catalyst in the TRPTC system.In this dissertation, the TRPTC was applied in the hydroformylation of higher olefins catalyzed by the cobalt complex. The thermoregulated phase-transfer cobalt complexes were used as the catalyst. The catalytic performance and the reusability of the catalysts in the aqueous-organic biphasic hydroformylation of higher olefins were investigated.The thermoregulated phosphine ligand L1, containing a polyoxyethylene chain was prepared, as well as two new thermoregulated phosphine ligands L2and L3were designed and prepared according to the feature of phosphines in the homogeneous cobalt-phosphine catalysts (see Fig.2.1). And three thermoregulated phase-transfer cobalt complexes (Co2(CO)8/Li, Co2(CO)8/L2, Co2(CO)8/L3) were generated in situ. The catalytic performance of the three thermoregulated phase-transfer cobalt complexes, the effects of different reaction conditions and the reusability of the catalysts were investigated. The results showed that the activity and the selectivity of the thermoregulated phase-transfer cobalt complex catalysts in the aqueous-organic biphasic system were as high as those of the homogeneous phosphine modified cobalt carbonyl catalysts, and the yield of nonanals and nonanols was up to93%and the linearity reached85%. The hydrofromylation reaction was not influenced by the poor solubility of1-octene. After reaction, the aqueous phase containing the thermoregulated phase-transfer cobalt complex catalyst was reused directly without treatment in the recycling experiment. And after5cycles of the catalysts, the total TON reached365. And the catalytic performance of Co2(CO)8/L1and Co2(CO)8/L2catalysts were also investigated in the hydroformylation of C11-12mixed olefins. The results showed the linear C12-13aldehydes and alcohols were obtained predominately because of the isomerization activity of the catalysts, and the linearity reached69%and the yield of C12-13aldehydes and alcohols was up to86%. After5cycles of the catalysts, the total TON reached187.The formation of the thermoregulated phase-transfer cobalt complex catalyst from the cheap cobalt compounds and the thermoregulated phosphine ligand was explored. It was found that the catalytic activity of the cobalt complex catalysts, formed from cobalt acetate or cobalt acetylacetonate under the hydroformylation conditions, was equal to that of Co2(CO)8/Li catalyst. The preliminary study confirmed that the cobalt carbonyl complexes formed from the thermoregulated phosphine ligand L1and cobalt acetate or cobalt acetylacetonate under the hydroformylation conditions were the same as that from the thermoregulated phosphine ligand L1and Co2(CO)8.更多还原