Abstract
Syntheses and some reactions of highly coordinate organosilicon compounds as synthetic reagents, substituted by alkoxy groups, are described. Topics are (1) preparations of pentacoordinate allylsiliconates, isolated for the first time, as useful and storable reagents for regio-, chemo-, and stereoselective allylations of carbonyl compounds, (2) stereochemical outcomes of asymmetric allylation with optically active allylsiliconates which are interpreted by a six-membered cyclic transition state, (3) cross-coupling reactions of alkenylsiliconates with organic iodides and triflates catalyzed by a palladium complex in a stereoselective mode, and finally (4) chemo- and stereoselective reductions of carbonyl compounds using alkoxy-substituted hydridosiliconates derived from trialkoxysilane and alkali metal alkoxides or lithium salts of amino alcohols, and new catalytic asymmetric reductions of prochiral ketones using hydridosiliconates.
