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161.
SYNTHESIS AND CHARACTERIZATION OF A NOVEL REACTIVE LADDER-LIKE POLYSILSESQUIOXANE WITH LATERAL BROMOPHENYL GROUPS 总被引:1,自引:0,他引:1
HuiLi Shu-yanYu Zhong-rongShen Zhong-xingZhang Qing-huaDuan Jin-qiangJiang PingXie 张榕本 《高分子科学》2004,(5):445-451
A novel soluble, reactive ladder-like polysilsesquioxane (L) with lateral bromophenyl groups was synthesized successfully by stepwise coupling polymerization (SCP) method including preaminolysis, hydrolysis and polycondensation steps. The monomer 3-trichlorosilylpropoxy-4-bromobenzene (M) was first prepared via hydrosilylation reaction catalyzed by dicyclopentadienylplatinum (Ⅱ) dichloride (Cp2PtCl2). The title polymer (L) was characterized by ^1H-NMR, ^29Si-NMR,FTIR, X-ray diffraction (XRD), DSC and vapor pressure osmometry (VPO). The experimental results indicate that the polymer (L) possesses a typical ladder-like structure. 相似文献
162.
163.
Bogdan Marciniec Hieronim Maciejewski Karol Szubert Magdalena Kurdykowska 《Monatshefte für Chemie / Chemical Monthly》2006,137(5):605-611
Summary. The hydrosilylation of 1-heptene, allyl glycidyl ether and, allyl polyether by heptamethylhydrotrisiloxane and poly(hydro,
methyl)(dimethyl)siloxane catalyzed by rhodium(I) complexes (particularly [{Rh(μ–OSiMe3)(cod)}2]) in imidazolium ionic liquids (especially [TriMIM]MeSO4) gives heptyl and glycidyloxy functional (poly)siloxanes and silicone polyethers with high yield and selectivity. The catalytic
system based on rhodium siloxide can be easily separated from the product and successfully reused up to five times. 相似文献
164.
165.
A new class of chiral ligands, e.g., (−)-9, based on the benzoxazine nucleus, has been designed and synthesized in three steps from the commercially available starting materials salicylamide and (−)-menthone. Application of (−)-9 in the palladium catalyzed-allylic substitution of 1,3-diphenyl-2-propenylacetate with dimethyl malonate gave enantioselectivities of up to 62%ee. Ees of 42% and 20% in asymmetric hydrosilylations and diethylzinc additions, respectively, were also obtained. 相似文献
166.
VULCANIZATION KINETICS OF SILICONE RUBBER 总被引:4,自引:0,他引:4
Vulcanization rate of silicone rubber with the aid of organic peroxide or hydrosilylation agent was studied by using oscillation disk rheometer. It was found that the process of network formation would take place through one, two or three steps depending on the structure of the reactants. The effect of phenyl group, vinyl terminals on polysiloxane chain and the functionality of silylation agent was also studied. 相似文献
167.
Magnus Gustafsson 《Journal of organometallic chemistry》2004,689(2):438-443
The regioselectivity in the Rh catalysed 1,4-hydrosilylation of isoprene was investigated. Variation of solvents and temperature did not significantly affect the isomer distribution between tail-product (I) and head-product (II). The choice of ligands had the greater influence, where RhI-based catalysts with the strong electron withdrawing ligand CO favoured production of isomer II, while RhI catalysts with strong electron donating ligands (for example triarylphosphines) gave isomer I as the main product. In contrast to the square planar carbonyl complex RhCl(CO)(PPh3)2, the square planar thiocarbonyl complex RhCl(CS)(PPh3)2, gave I as the major isomer. 相似文献
168.
Pavel Arsenyan Kristine Oberte Kira Rubina Sergey Belyakov 《Tetrahedron letters》2005,46(6):1001-1003
The reaction of 4-methyl-5-ethoxycarbonyl-1,2,3-selenadiazole with (PPh3)4Pt leads to the formation of a new platinum-containing heterocyclic system. It was found that the selenoplatinum complex is a selective catalyst for the hydrosilylation of terminal alkynes to yield β-(Z)- and β-(E)-silylethylenes. 相似文献
169.
Dong-won Lee 《Tetrahedron letters》2004,45(28):5415-5417
Air and moisture stable copper(II) salts can be used to catalyze the hydrosilylation of aromatic ketones. The combination of catalytic amounts of copper(II) acetate or copper(II) acetate monohydrate (Cu(OAc)2·H2O) and BINAP in the presence of organosilanes as the stoichiometric reducing agent generates an active catalyst for the reduction of ketones. 相似文献
170.
A modified method of preparing crown functionalized linear polysiloxane has been described.4'-allylbenzo-15-crown-5 was subjected to hydrosilylation with methyldichlorosilane,followed bypolycondensation with silanol-terminated polydimethylsiloxane to give the title crownfunctionalized linear polysiloxane. It was found that the polysiloxane could be coordinated withplatinum salt to form platinum complex, which could catalyze the hydrosilylation of olefins withtriethoxysilane efficiently. 相似文献