Synthesis of polyfunctional triethoxysilanes by ‘click silylation’

The copper-catalyzed ‘click silylation’ has been exploited for the chemical modification of γ-azidopropyltriethoxysilane (AzPTES) with a wide range of terminal alkynes (1a–1v) in a one-pot operation. The novel 1,2,3-triazole-triethoxysilane derivatives (2a–2v) were synthesized by this procedure and comprehensively characterized by IR spectra, ¹H and ¹³C NMR, and HRMS studies.     

Spectroscopic studies of triethoxysilane sol-gel and coating process

Silica sol-gels have been prepared under different conditions using triethoxysilane (TES) as precursor. The prepared sol-gels have been used to coat aluminum for corrosion protection. Vibrational assignments have been made for most vibration bands of TES, TES sol-gel, TES sol-gel-coated aluminum and xerogel. It has been noticed that air moisture may have helped the hydrolysis of the thin coating films. Xerogels have been obtained from the sol-gel under different temperature conditions and the resulting samples have been characterized by using infrared and Raman spectroscopic methods. IR data indicate that the sol-gel process is incomplete under the ambient conditions although an aqueous condition can have slightly improved the process. Two nonequivalent silicon atoms have been identified from the collected (29)Si NMR spectra for the sol-gel, supporting the result derived from the IR data. The frequency of SiH bending vibration has been found to be more sensitive to the skeletal structure than that of the SiH stretching vibration. A higher temperature condition could favor the progression of hydrolysis and condensation. A temperature higher than 300 degrees C would cause sample decomposition without seriously damaging the silica network. From infrared intensity measurements and thermo-gravimetric analyses, the fractions of incomplete hydrolysis and condensation species have been estimated to be 4% and 3%, respectively. Electrochemical data have shown that the sol-gel coating significantly improves the corrosion protection properties of aluminum.     

直接法制备三乙氧基硅烷催化剂的研究进展

综述了直接法合成三乙氧基硅烷的研究进展,着重对直接法的反应机理和催化剂组分的筛选进行了分析讨论.同时介绍了以三乙氧基硅烷为原料,合成烯丙基三乙氧基硅烷、γ-(2,3-环氧丙氧)丙基三乙氧基硅烷、苯乙基三乙氧基硅烷、五乙氧基二硅烷等衍生物的工艺,提出了催化剂制备过程中存在的问题及研究方向.     

(Dicyclopentadiene) platinum(II) dichloride: An efficient catalyst for the hydrosilylation reaction between alkenes and triethoxysilane

(Dicyclopentadiene) platinum(II) dichloride was found to be an efficient hydrosilylation catalyst (homogeneous) upon a wide variety of functionalized alkenes and alkenes terminated with chemical moieties (diphenyl amino-, N-carbazol- and N-isoindoline-1,3-dione-). It is noteworthy that the hydrosilylation of aminated alkenes with triethoxysilane exhibited the yield of over 70% and the selectivity (γ-isomer/β-isomer) of more than 3/1. Due to steric hindrance lowering Markovnikov probability, the alkenes with big terminal moieties (diphenyl amino-, N-carbazol- and N-isoindoline-1,3-dione-) presented the high ratio of anti-Markovnikov isomers. The strategy of the hydrosilylation of the protected diamino chelating alkene was developed.     

乙炔和三乙氧基硅烷的硅氢加成反应研究

制备了氯铂酸-异丙醇、氯铂酸-聚甲基乙烯基硅氧烷和氯铂酸-三苯基膦三种催化剂,评价了它们在乙炔与三乙氧基硅烷的硅氢加成反应中的催化活性及选择性;并考察了反应温度、乙炔流量、氯铂酸-聚甲基乙烯基硅氧烷与三乙氧基硅烷摩尔比、PPh3/H2PtCl6摩尔比等因素对产物收率的影响.结果表明,氯铂酸-聚甲基乙烯基硅氧烷对该反应表现出较高的催化活性,在催化剂与三乙氧基硅烷摩尔比为1.2×10-4∶1,T=80℃,乙炔流量=120 mL/min的条件下反应,产物乙烯基三乙氧基硅烷的选择性为100%,收率可达97.5%.