Silicon-phosphorus cages

Keywords silicon-phosphorus cage, silicon-arsenic cage, synthesis... 

Summary The preparation of two novel silicon-arsenic cages with a bicycloheptane structure (1) and a tricyclononane structure (2) is described. Furthermore we report the synthesis of a new anionic silicon-phosphorus cage with a bicyclooctane skeleton (3). Its reaction with chlorotrimethylsilane gives 4. X-ray stractures and NMR data of all newly synthesized compounds are presented. 

Silicon-Phosphorus, -Arsenic, -Antimony, and -Bismuth Cages Syntheses and Structures... 

One method for the synthesis of cyclic silicon-phosphorus compounds is the reaction of alkaliphosphides with dichlorosilanes [1]. Using sodium/potassium phosphide, -arsenide, -antimonide and -bismutide Na3E/K3E (E = P, As, Sb and Bi) [2] with various di-, tri-, and tetrachloroorganosilanes, cages of the following types (Fig 1.) have been synthesized so far. 

Preparations and X-Ray Structures of some Silicon-Phosphorus and Silicon-Arsenic Cages... 

K. Hassler, Silicon-phosphorus, -arsenic, -antimony, and -bismuth cages syntheses and shuctures, in Organosilicon Chemistry — From Molecules to Materials (Eds N. Auner, J. Weis), VCH Weinheim, 1996, p. 203. 

Silicon-phosphorus heterocyclic structures (rings, cages, polycyclic ladders) are also well investigated. ... 

Tekautz G, Baumgartner J, Dransfeld A, Hassler K (2007) Silicon-phosphorus and silicon-arsenic cage compounds with bicyclo[2.2.1]heptane, bicyclo[3.2.1]octane and tricyclo [3.3.3.1.0 ]nonane backbones. Eur J Inorg Chem 4071... 

Recently some bicyclo and cage structures based on P—P bonds have been obtained by reacting a mixture of RPCl and PCI3 with magnesium. Only the phosphorus skeletons are shown (Fig. 4.12). These discoveries show that the chemistry of catenated phosphorus derivatives, like that of catenated silicon compounds, is much more diverse than was imagined even ten years ago. 

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