Trichloroethoxycarbonyl chloride

It has been reported that the reaction of NN-dimethylfuntumine (la) with trichloroethoxycarbonyl chloride gave the elimination product (2), in high yield, rather than the expected urethane (lb).4 Under the same reaction conditions the epimeric dimethylamino-pregnane derivatives (3a) and (3b) both gave the olefin (4), accompanied by minor amounts of the expected urethanes (3c) and (3d) respectively. The reaction of conessine (5a) with Cl3CCH2OCOCl yielded only the urethane (5b).4... 

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. ... 

TcecCl also TrocCl 2,2,2-Trichloroethoxycarbonyl chloride (2,2,2-trichloroethyl chloroformate)... 

Trichloroethoxycarbonyl chloride (1.00 g, 4.72 mmol) was added to a solution of 2-amino-2-deoxy-0-glucopyranose hydrochloride (0.68 g, 3.16 mmol) and NaHCOa (0.68 g, 8.1 mmol) in water (10 ml) at 0 C. After 2 h the mixture was allowed to attain room temperature and was then stirred overnight. After filtration, the colourless precipitate was washed with water and diethyl ether and then recrystallized from EtOH to give 2-deoxy-2-(2,2,2-trichloroethoxycarbonylamino)-D-glucopyranose (0.98 g, 87%) m.p. 183-184°C (dec.) [a] +50° (cO.84, MeOH). 

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). 

The thiol (271) obtained by hydrolysis of the requisite thiazoline (270) was acylated with trichloroethoxycarbonyl chloride followed by treatment with triethylamine to yield (298) (Arafani and Hashimoto, 1980). 

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

The j3,/8,j3-trichloroethoxycarbonyl group has proved useful in the synthesis of optically active 1,2-diacylglycerols (5).1 Thus 1,2-isopropylidene-sn-glycerol (1) is treated with /3,/3,/3-trichloroethyl chloroformate and pyridine in dry chloroform. The isopropylidene group of the product (2) is then cleaved with dilute hydrochloric acid to give sn-glycerol-3-j8,/3,)3-trichloroethylcarbonate (3). This is then acylated with an acyl chloride (pyridine-chloroform) (4) and in the fined step the protective group is cleaved with activated zinc in acetic acid.2... 

This can be used during the preparation of unsaturated 1,2- and 2,3-diacyl-5n-glycerols. The 2,2,2-trichloroethoxycarbonyl group is introduced on to the free primary hydroxyl group as the carbonyl chloride. It is retained, without migration, when the isopropylidene group is removed and is, itself, removed with zinc in acetic acid at room temperature (Pfeiffer era/., 1968). 

---