Trichlorosilanes special

FIGURE 4.4 The production of polycrystalline silicon for the eleetronics industry involves several ehemieal steps aimed at the reduetion of impurities. These inelude (1) reaction of metallurgical grade silicon to produce a mixture of chlorosilanes, (2) distillation of trichlorosilane, and (3) reduction of trichlorosilane to polycrystalline silicon. Excerpted by special permission from Chemical Engineering, June 10, 1985. Copyright 1985 by McGraw-Hill, Inc., New York, NY 10020. 

Polyhedral silsesquioxanes present themselves as models for surface-modified silica gels [1]. With the exception of some special cases octasilsesquioxanes normally are obtained by hydrolysis of trichlorosilanes or trialkoxysilanes. Cage rearrangement of octasilsesquioxanes is a new method to prepare mixtures of octa-, deca- and D2d-dodecasilsesquioxanes [2, 3]. These mixtures have to be separated to analyze the single compounds. A new possibility for analyzing silsesquioxanes or silsesquioxane mixtures is given by MALDI-TOF-MS. 

Substitution reactions of trichlorosilane are rare, and occur under special conditions. Monochloroethene reacts with trichlorosilane upon brief heating to 400-500 C to give trichlorovinylsilane [169] (Eq. 3.57) ... 

Bis(phosphinoylmethyl)ainines (58) are useful precursors of bidentate P-ligands (59) obtained after double deoxy-genabon by silanes, e.g., trichlorosilane that could be used for the synthesis of ring platinum complexes (60) by reaction with dichlorodibenzonitrile platinum (Scheme 22) [75-78]. Ring Pt complexes are special heterocycles that may be regarded potential catalysts in homogeneous catalysis. 

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