The Modified Sakurai and Related Reactions

Most organosilicon compounds (silyl ethers, silylenolethers, allyl- and vinyl-silanes) are stable enough to be easily prepared, handled and stored with a minimum of precautions. Whilst silyl ethers are mainly considered as protected alcohol 

Multicomponent Reactions. Edited by Jieping Zhu, Hugues Bienayme Copyright 2005 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 3-527-30806-7 

This addition occurs on aldehydes and ketones and is favored by the strong affinity of the fluoride anion for silicon (Si-F dissociation energy = 140 kcal mol-1) 

These two methods of activation are complementary. The Lewis-acid (pull) procedure is most efficient for aliphatic carbonyls and the Lewis-base (push) protocol for the aromatic ones. It is noteworthy that TBAF, which often contains residual water, does not inhibit the reaction. 

The acetal 14, activated by the iodotrimethylsilane 17, produces the oxonium cation 16 which can be intercepted by allylsilane 1 yielding homoallylic ether 15, one equivalent of methoxytrimethylsilane 18 and the catalyst 17. 

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