Trimethylsilyl trichloroacetate

Trimethylsilyl trichloroacetate, K2CO3, 18-crown-6, 100-150°, 1-2 h, 80-90% yield.This reagent silylates phenols, thiols, carboxylic acids, acetylenes, urethanes, and /3-keto esters, producing CO2 and chloroform as byproducts. 

Trimethylsilyl trichloroacetate is a useful reagent for the A-trimethylsilylation of amines284. The combined action of primary aliphatic or aromatic amines and trimethylsilyl cyanide on aliphatic or aromatic aldehydes yields a-amino nitriles (equation 93)285,286. 

As the alcohol is not formed, there is no need to use sterically hindered alkoxides. This reaction is usually carried out in pentane or in an excess of alkene at 0 to 10 °C and is recommended for the preparation of thermally unstable 1,1-dichlorocyclopropanes. An interesting modification for the synthesis of 1,1-dichlorocyclopropanes which eliminates strongly alkaline medium, utilizes trimethylsilyl trichloroacetate and potassium fluoride in the presence of a catalyst (a quaternary ammonium salt or a crown ether),... 

Several analogues of Mosher s acid have been developed for determining the stereo-chemistry. In addition, a modified Mosher s method has been used to determined the absolute configuration of some natural products. Moreover, the preparation of MTPA has been improved to one-pot synthesis by the addition of trimethylsilyl trichloroacetate to a,Q, Q -trifluoroacetophenone and subsequent hydrolysis. ... 

Trichloroacetic acid, pKa of. 759 Trifluoroacetic acid, pKa of, 756 Trifluoromethylbenzene, electrostatic potential map of, 565 Triglyceride, see Triacylglycerol, 1061 Trimethylamine, bond angles in, 919 bond lengths in, 919 electrostatic potential map of, 921 molecular model of, 919 Trimethylammonium chloride, IR spectrum of, 953 Trimethylsilyl ether, cleavage of, 627-628... 

Kusumoto and coworkers have found that the treatment of hemiacetal 1 with trifluoro- or trichloroacetic anhydride 94 (1 equiv) and trimethylsilyl perchlorate (0.2 equiv) selectively provides the corresponding anomeric ester intermediate 91 [152], Hemiacetal acylation occurs even in the presence of the alcohol acceptor. With Lewis acid assistance, the glycosyl ester intermediate is displaced to provide disaccharide products in good yields. This transformation allowed the synthesis of disaccharides 98 (81%) and 99 (91%). In some cases, acetic anhydride has been used as the electrophilic activator of hemiacetal donors and the reaction with thiol acceptors yields S-linked glycosides [153,154],... 

Many mycotoxins, including the trichothecenes and fumonisins, have polar hydroxyl groups that can be readily derivatized to trimethylsilyl ethers with such reagents as trimethylsilyl chloride or hexa-methyldisilazane and N-trimethylsilylimidazole. Alternatively polyhalogenated acyl derivatives can be made, using reagents such as trichloroacetic anhydride or heptafluorobutyric anhydride, which are especially useful in conjunction with ECDs. 

The following materials may be obtained as reagent or other similar quality grade, and used without further purification chloroform, 2,4,6-collidine, dichloromethane, dicyclohexylcarbodiimide, l-(3-dimethyl-aminopropyl)-ethylcarbodiimide,4-dimethylaminopyridine, ethanol, 1 -methylimidazole, ninhydrin.p-nitrophenol, pentachlorophenol, piperidine, succinic anhydride, trichloroacetic acid, triethylamine, and toluene. The following reagents may be used as purchased, but must be stored tightly sealed to avoid undue exposure to moisture acetic anhydride, 3-aminopropyltriethoxysilane, and trimethylsilyl chloride. 

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