Synthesis Of Graphite Oxide-supported Platinum Complexes And Their Properties In The Hydrosilylation Of Olefins With Triethoxysilane

As a kind of high-performance chemical material, organosilicon material arewidely used in electronic electricity, aerospace, automobile industry,construction industry, medical equipment and daily-use chemicals. And hydrosilylation is an important organic transformation for the construction of Si-Cbonds and plays a vital role in the synthesis of functional silanes and silicon polymers.Speier’s catalyst and Karstedt’s catalyst are the efficient homogeneous industrialcatalysts, but suffers from some drawbacks such as deactivation and difficult recoveryand recycling of the catalyst. Thus, development of efficient solid-basedheterogeneous catalyst for hydrosilylation reaction is highly desirable owing to itseasy separation, reusability and environment-friendly.Graphite oxide is an extraordinarily versatile carbon material, and can be easilymodified due to its various oxygen containing functional groups (hydroxyl, carboxyl,and epoxy groups). Therefore, graphite oxide performs as an excellent supportingmaterial for immobilizing homogenous catalysts. Herein, we prepared two novelkinds of graphite oxide-supported heterogeneous catalysts for hydrosilylationreaction.1. In the first part of this paper, a graphite oxide-supported Karstedtheterogeneous catalyst was prepared from vinyltriethoxysilane via immobilization ongraphite oxide, followed by reacting with chloroplatinic acid. The catalyst wascharacterized by XRD, FT-IR, TGA and TEM techniques. The catalytic results showthat the catalyst was active for hydrosilylation of olefins with triethoxysilane, inparticular for the aliphatic with triethoxysilane.90.4%yield in favor of β-adduct wasobtained when1-octene reacted with triethoxysilane at60°C after60min. Thecatalyst can be recycled seven times without significant loss of catalytic activity andselectivity.2. In the second part of this paper, we prepared graphite oxide-supportedbidentate phosphine platinum complex (GO-P-Pt) as follow: graphite oxide wasfirstly treated by3-aminopropyltriethoxysilane, and followed functionalized with diphenylphosphinomethanol and potassium chloroplatinate. The resulting GO-P-Ptcatalyst was characterized by elemental analysis, FT-IR and XRD. It was found thatthe catalyst exhibited high activity for the hydrosilylation of olefins withtriethoxysilane. When the hydrosilylation reaction was carried out at100°C,decyltriethoxysilane was obtained in93%yield after180min. GO-P-Pt catalyst alsoexhibited high operational stability with no dramatic loss of catalytic activity andselectivity even after four successive times.