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Please login or sign up for a free trial to access the full content. Method 2: Oxidative Deprotection of Silyl Ethers

DOI: 10.1055/sos-SD-026-00003

von Angerer, S.Science of Synthesis, (200526111.

Trialkylsilyl groups are widely used as protecting groups for alcohols. If the protected alcohol needs to be converted into a ketone or aldehyde, a one-step or one-pot reaction including both deprotection and oxidation would be desirable. A variety of methods have been elaborated that achieve this goal and are the subject of a review article.[‌8‌] Some of the oxidation procedures described previously can also be applied to the oxidation of silyl ethers if these alcohol derivatives are susceptable to cleavage under the reaction conditions. Trimethylsilyl ethers of nonactivated secondary alcohols can be oxidized to the corresponding ketones with chromium(VI)-based reagents such as the Jones reagent.[‌75‌,‌76‌,‌413‌,‌431‌‌434‌] A more powerful oxidant has been obtained by the combination of Jones reagent with potassium fluoride.[‌435‌] The fluoride ion probably facilitates the cleavage of the SiO bond. A typical example of this reaction is the formation of (5S)-3,3,5-trimethylcyclohexanone (166) (Scheme 118).

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