Esters trichloroethoxycarbonyl

Carboxylation. Bredereck s reagent has been used in a simple synthesis of L-y-carboxyglutamic acid (S), an unusual natural amino add present in prothrombin and believed to be involved in elotting. The starting material is the lactam 1 derived from L-glutamic acid and available commercially. It is converted by reaction with this reagent into the enamide 2. Reaction with 2,2,2-trichloroethoxycarbonyl chloride transforms 2 into the trichloroethyl ester 3 in moderate yield. The synthesis of 5 is completed by reaction with benzyl alcohol and triethylamine followed by hy drogenolysis. ... 

Even 6,1-lactones of hexuronic acids,785,786 for example, 2,3,4-tri-O-acetyl-jS-D-glucopyranurono-6,1-lactone785 (254) and the corresponding 2,3,4-tri-0-(2,2,2-trichloroethoxycarbonyl) ester,787 may be considered to be 1,6-anhydrohexose analogs however, they behave as ordinary lactones. 

They also demonstrated that inexpensive molecular iodine can be used as a cheap, nontoxic, general, and fast catalyst for one-pot tandem acetalation-esteri-fication reactions of glycosides in good to excellent yields without the need of purification after every reaction step. Further, the addition of catalytic DMAP can be used to accelerate the esterification step and thus shorten the reaction times. The method is mild and compatible with different thioglycosides and 0-glycosides, applicable to the formation of 4,6-0-benzylidene and 4,6-0-p-methoxybenzylidene acetals in tandem reaction with either 2,3-0-di-acetate or 2,3-0-di-benzoate esters and also amenable to commonly used amino-protecting groups (e.g., phthalimides and 2,2,2-trichloroethoxycarbonyl chloride). 

Carbonochloridic acid 2,2,2-trichloroethyl ester, 9CL Chloroformic acid 2,2,2-trichloroethyl ester, 8CL Trichloroethoxycarbonyl chloride [17341-93-4]... 

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