Trimethylsilyl chlorochromate alcohols

Potassium hydroxide, 258 Trimethylsilyl chlorochromate, 327 of carbon-carbon double bonds substituted by heteroatoms m-Chloroperbenzoic acid, 76 of oximes to carbonyl compounds Lithium aluminum hydride-Hexa-methylphosphoric triamide, 159 Titanium(III) chloride-Diisobutylalu-minum hydride, 303 Trimethylsilyl chlorochromate, 327 of protected alcohols Chlorodimethylthexylsilane, 74 Formic acid, 137 p-Methoxyphenol, 181 of thioacetals and -ketals Methoxy(phenylthio)trimethyl-silylmethane, 182... 

Potassium nitrosodisulfonate, 258 Trimethylsilyl chlorochromate, 327 By hydrolysis of acetals or thioacetals Amberlyst ion-exchange resin, 152 Methylthiomethyl p-tolyl sulfone, 192 By isomerization of allylic alcohols N-Lithioethylenediamine, 157 By oxidation of aromatic side chains Trimethylsilyl chlorochromate, 327 From oxidative cleavage of alkenes [Bis(salicylidene-7-iminopropyl)-methylamine]cobalt(II)... 

The mixture of chromium trioxide with one equivalent of trimethylsilyl chloride, with no solvent added, results in the formation of an explosive red liquid that is soluble in dichloromethane or tetrachloromethane.428 It is suggested, with no spectroscopic evidence, that it consists of trimethylsilyl chlorochromate [Me3Si-0-Cr(0)2-Cl]. This compound, which can safely be used in organic solvents, is able to oxidize alcohols to aldehydes or ketones, and interacts with r-butyldimethylsilyl ethers producing deprotection, followed by oxidation of the liberated alcohol.138 Compounds analogue to trimethylsilyl chlorochromate are also able to oxidize alcohols, although they possess lesser reactivity. They can be prepared by reaction of chromium trioxide with dimethyldichlorosilane and diphenyldichlorosilane.428b... 

Trimethylsilyl chlorochromate gives good yields for secondary alcohols and benzylic alcohols, but saturated primary alcohols give complex mixtures. It will also oxidise thiols to disulfides, and cleave... 

Dicarboxypyridinium chlorochromate (2,6-DCPCC)392 possesses an acidic character that allows the in situ deprotection and oxidation of alcohols, protected as tetrahydropyranyl and trimethylsilyl ethers. 2,2 -Bipyridinium chlorochromate (BPCC)393 contains a ligand that complexes efficiently with the reduced chromium species, generated during the oxidation of alcohols, allowing for a substantial simplification of the work-ups. For this reason, it enjoys a popularity among chlorochromates surpassed by only PCC. 

Oxidations by pyridinium chlorochromate resemble those by dipyridine chromium(VI) oxide, both in scope and the mild conditions required. At room temperature, primary alcohols give aldehydes [604, 605], secondary alcohols afford ketones [605], allylic and benzylic methylene groups are oxidized to carbonyl groups [606, 6d7], enol ethers are converted into esters [608] or lactones [609], trimethylsilyl ethers of diphenols are transformed into quinones [610], and alkylboranes are converted into aldehydes (yll]. 

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