Propargyl, and Benzyl Silanes

Propargyl, and Benzyl Silanes. - Several new procedures for the preparation of allyl silanes have appeared. Iridium (II) and rhodium (I) catalysts are effective in isomerising alkenes (166) to allyl 

Vinyl silanes have also been prepared in this way. Optically 

Electrophilic attack on allyl silanes represents one of their most commonly used modes of reaction. The relative reactivity of allyl silanes and alkenes towards diarylmethyl cations has been used to calculate the value of the 0- effect of a trimethylsilyl group. 

The introduction of a 0- SiMe3 residue increases the reactivity of an alkene towards Ph CH by a factor of 30700, and the stabilising fief feet has been estimated at approximately 4.2 kcal mol 

Trost et al. have prepared the silyl-substituted trimethylene- 

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