Hydrosilylation Of Phenoxymine Cataivst Ligands Containing Unstaturated Substituent

Coordination polymerization catalyst as the core of polyolefin is very important. Each improvement of polyolefin industry is closely related to coordination olefin polymerization catalysts. After Ziegler-Natta and metallocene catalysts, non-metallocene catalyst is the third stage of development. Because the suitable ligand and coordination metal is very extensive, this kind of catalyst can be used to prepare many kinds of novel polymers with different structure. And some catalysts have been industrialized. In the last decade, much attention in the academic and industry fields has been paid to phenoxyimine former transition metal catalysts (FI catalyst) which bearing the character of high temperature "active" polymerization. But there are some problems with the homogeneous non-metallocen catalyst, such as bad controlling of polymer morphology, sticky kettle phenomenon. It can’t be directly used in gas or slurry process. So the researches about the immobilization of these catalysts which can overcome the problems are of great importance and value.In this dissertation, in order to prepare immobilization catalysts for olefin polymerization, a series of phenoxyimine ligands containing unsaturated bond were synthesized according to the requirement of novel efficient Fujita catalyst to the ligands. And then hydrosilylation study of these ligands was carried out. Finally, a series of phenoxyimine ligands containing-Si(OEt)3which could be further used as precursors for covalent-bonded heterogeneous catalysts were obtained.In the first part of this paper, by considering the structure request of high efficient Fujita catalysts and the covalent-bonded immobilization, a series of phenoxyimine ligands containing unsaturated bond were designed and synthesized, including allyl-and St-phenoxyimine ligands. For allyl-phenoxyimine ligands, the corresponding products which have been induced a allyl-substituent group were obtained, by the Schiff-base reaction between3-allylsalicylide and2,6-difluoroaniline.2,3,5,6-tetrafluoroaniline,2,3,4,5,6-pentafluoroaniline, respectively. The purities of the products all reached98%. For St-phenoxyimine ligand, the corresponding ligand which has been induced a St-substituent group was prepared by Suzuki and Schiff-base reaction, successively. Meanwhile,4-(p-vincyl)phenyl-2,6-difluoroaniline and distyrene whose purities reached98%were prepared. These two compounds can be further used in the new reaction route and researches of the hydrosilylation reaction’s characters.The second part are divided into two parts, discussing the hydrosilylation reaction of allyl-and St-phenoxyimine ligand respectively. The reasons of the generation of byproducts and the best reaction condition were discussed deeply.Three kinds of allyl-phenyoxyimine ligands reacted with triethoxysilane. The conversions of all ligands reached100%, while the products’ selectivities were between51～58%, followed by2F-allyl-ligand>4F-allyl-ligand>5F-allyl-ligand. By column chromatography, the above pure products were obtained. After the byproducts were confirmed by’H-NMR and GC-MS, the possible byproducts’ generation mechanisms were proposed. Meanwhile, the best reaction condition were also obtained via2F-allyl-ligand as the sample:the concentration of ligands in toluene (0.5mmol/ml), TES(1.2times as much as ligands), Pt-PMVS(50ppm),60～80℃,6hours. And products with the selectivity of58.8%could be prepared. However, the-OH protecting action did not have any improvement of selectivity. But the conversion of the reactants declined. In addition, by comparing, we find that the hydrosilylation between these ligands with1,1,1,3,5,5,5-heptamethyltrisiloxane (MDHM) bearing much higher selectivity, reached92～96%. And by purigying, three silanization products whose purities reached98%were obtained.The pure product hasn’t been got by the reaction route of the hydrosilylation between N-(Salicylidene)-2,6-difluoro-4-styrylaniline and TES directly. Because there are many side reactions resulting in low selectivity of the target product. And then, a series of hydrosilylation reactions of compounds containing-St were studied. By comparison, we find that:(1) When reacted with TES, the ligands conversion and product selectivity were arranged in the order styrene>4-(p-vincyl)phenyl-2,6-difluoroaniline>distyrene>N-(Salicylidene)-2,6-difluoro-4-styrylaniline.(2) When reacted with MDHM, the conversion and selectivity of styrene were all100%. However, other three compounds (except0.5%of distyrene) all didn’t have any reactions.(3) TES was much easier to react with these St-compounds than MDHM. According to the results above, we prepared this ligand which contained-Si(OEt)3by a new route:1. Hydrosilylation between4-(p-vincyl)phenyl-2,6-difluoroaniline and TES, and the pure product was prepared;2. Schiff-base reaction between the product was obtained in step1and3-allylsalicylidene. Finally, the ligand containing-Si(OEt)3was got and the purity reached98%. The best reaction condition:4-(p-vincyl)phenyl-2,6-difluoroaniline(2mmol), TES(3mmol), Pt-PMVS(50ppm), toluene(10ml),60℃,7h. The conversion reached100%and the selectivity was95.2%.In the last part of this paper, we chose7kinds of ligands which was synthesized from the ligands obtained in part1and2, and prepared their correspongding catalysts for polymerization of olefin. The results showed as following:The atom F had much influence to catalysts’ activity. The catalysts with meta-F and para-F had much higher activity than catalysts with ortho-F. However, the "live" character of the ortho-F catalyst was the best, and the MWD also was narrowest. The introducing of siloxy group not only decreased catalysts’activity, but also destroyed the "live" character, making MWD of PE wider. As a result, they could be used as a model of silica terthring supported catalyst, to study the surface catalytic mechanism of it.