Metal containing organosilane

Metal-containing organosilanes are versatile reagents from two synthetic viewpoints. Synthetic reactions of the silicon functionality provide an efficient method for the preparation of polyfunctional organometallic reagents, whereas synthetic... 

PolyferrocenylsUanes are an interesting class of metal-containing polymers wiffi a mainchain consisting of alternating ferrocene and organosilane units. " Well-defined diblock copolymers containing polyferrocenylsilane segments are readily... 

Although organosilanes appear to react slowly (if at all) with water alone, in the presence of acids or bases (e.g., alkali metal hydroxides), reactions to give a silanol and H2 are rapid, with bases being particularly powerful catalysts. The evolution of H2 in this type of reaction may be used as both a qualitative and a quantitative test for Si-H bonds, and the mechanism of the acid and the base hydrolysis has been discussed in detail (30,31). This hydrolytic method is not very common for the preparation of silanols that are to be isolated, because both acids and bases catalyze the condensation of silanols to siloxanes, and therefore, only compounds containing large substituents are conveniently made in this way. If an anhydrous alkali metal salt is used, a metal siloxide may be isolated and subsequently hydrolyzed to give the silanol [Eq. (10)] (32). 

As part of our studies on a-metalated organosilanes, we use (aminomethyl)(lithiomethyl)silanes of the general type A [1]. Systems of types B and C containing defined stereochemical information could be synthesized starting from either chiral amines or from 5i-chiral silanes. A new structural motif (D) arises if the stereogenic center is adjacent to silicon (preferably as part of a rigid system). The goal of these studies was the synthesis of the enantiomerically pure, lithiated 2-silyl-substituted pyrrolidine E. 

The chemistry of silicon, germanium, and tin transition metal compounds has been the subject of several reviews (12, 180). Optically active silyl ligands have been introduced in a transition metal complex by reaction of chiral functional organosilanes. However chiral silyl ligands containing complexes are limited to a few metal centers we shall discuss in turn iron, cobalt, platinum, and manganese complexes. 

Recent work has involved the production of organosilanes and germanes, as small molecules or polymeric systems by electroreduction of the appropriate halo species at a reactive metal cathode (magnesium, aluminum, sometimes copper) in aprotic media. The same metal is used as a sacrificial anode, and the cell is undivided. Thus, with lithium perchlorate as electrolyte in THE solvent, a dichlorosilane such as PhMeSiCl2 gives a polysilane of Mn -- 3000 in 22% yield. This contrasts with earlier work at Hg cathodes in divided cells, where Si-0-containing polymers and cyclotetrasilanes were obtained. Simultaneous... 

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