Boron-Functionalized Carbosilanes: Insertion of Carborane Clusters into Peripheral Silicon Atoms of Carbosilane Compounds

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• 作者：Rosario Nú ; ñ ; ez ; Ará ; ntzazu Gonzá ; lez-Campo ; Clara Viñ ; as ; Francesc Teixidor ; Reijo Sillanp&auml ; &auml ; and Raikko Kivek&auml ; s
• 刊名：Organometallics
• 出版年：2005
• 出版时间：December 19, 2005
• 年：2005
• 卷：24
• 期：26
• 页码：6351 - 6357
• 全文大小：157K
• 年卷期：v.24,no.26(December 19, 2005)
• ISSN：1520-6041

文摘

Two families of carborane-containing star-shaped carbosilane molecules have beensynthesized. Three different carborane cages 1-R-1,2-C₂B₁₀H₁₁, in which the R group possessesdifferent bulkiness (R = H, Me, Ph), have been introduced on the carbosilane peripherythrough C_cluster-Si bonds. The first family, 1-3, is derived from a chlorosilane that containstwo carbon atoms as the branch point (1G_V-Cl), whereas in the second one, 4-6, the branchlength has been changed (1G_A-Cl) in order to study the size and flexibility of the compoundin both the reaction with carboranes and the final products. Two different methods havebeen used for their preparation: (a) the nucleophilic substitution of the periphery Si-Clfunctions with the corresponding carborane monolithium salt; (b) the hydrosilylation reactionof tetravinyl or tetraallylsilane with the carboranylsilanes 1-Me₂HSi-2-Me-1,2-C₂B₁₀H₁₀ (7)and 1-Me₂HSi-2-Ph-1,2-C₂B₁₀H₁₀ (8) catalyzed by Karsted's catalyst. The first method leadsto compounds that incorporate four carboranyl moieties covalently bonded to the peripheralSi atoms of a carbosilane core; nevertheless, differences in the final product yields areobserved depending on the carborane derivatives and the starting chlorosilane. Thehydrosilylation reaction was a highly efficient method to obtain 2 and 3 in large yield;nevertheless, this process was not successful to prepare 5 and 6. In addition, it is importantto emphasize that 1-3 were successfully isolated in crystalline form suitable for X-raydiffraction analyses. Furthermore, the X-ray crystal structure of the carboranylsilane 1-Me₂HSi-2-Ph-1,2-C₂B₁₀H₁₀ (8) is also reported.