Triphenyl silanol

The polarity of the Al-C bond allows easy derivatization of the five-coordinate aluminum alkyls by alkane elimination (Figure 9). For example, Salen aluminum alkyls LAlMe could be converted to dimeric or polymeric Salen aluminum phosphinates [LAl 02P(H)Ph ] 98 (n = 2 or oo, depending on the Salen ligand backbone)98,99 by reaction with phenyl phosphinic acid, Salen aluminum siloxides LA10SiPh3 by reaction with triphenyl silanol,96 or Salen aluminum alkoxides LAIOR by reaction with an alcohol.100... 

Structure [I] was quickly dismissed because of the reaction of A with iodine. While structure [II] was tenable for the unsaturated compound, this structure was reserved by him for Compound B. A number of factors ruled against isomers [III, IV, and V], including the improbability of their formation in the reaction mixture producing A, the fact that no triphenyl-silanol was obtained from the hydrolysis of A, and the fact that the same cyclic dioxide (18) could be obtained starting with either A or B. Hydrogen values, hydrolysis products, and behavior toward iodine eliminated isomers [VI] and [VII]. One other quite unlikely possibility for the structure of Compound A would be a cyclic conformation with a tri-phenylsilyl side chain [IX]. However, factors which rule against isomers [III, IV, and V], would also eliminate this configuration. 

The trimethylsilylated ylides (1), easily generated from trimethyl chlorosilane and ylides, react with aldehydes 2 to form vi-nylsilanes 3 (2,3). The vinylphosphonium silanolates 4 are also formed. Compounds 3 are versatile reagents for further reactions (4). The ylide J (with R1 =H) reacts with aldehydes 2 to give the dienes j). The oxidation of with the adduct 6, from triphenyl-phosphite and ozone, gives access to a generaT synthesis of acyl-silanes (trimethylsilylketones) (2). The silylated ylides react to form phosphonium salts 7 with halogen compounds. The salts 7.can be desilylated by fluorine ions. The disubstituted ylides JO Tormed can be converted in statu nascendi with aldehydes V[ into the tris-substituted olefin J2 (2,3). In the case of R3-I, vinyl... 

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