Trichloroacetyl chloride

Chloroacetyl chloride is manufactured by reaction of chloroacetic acid with chlorinating agents such as phosphoms oxychloride, phosphoms trichloride, sulfuryl chloride, or phosgene (42—44). Various catalysts have been used to promote the reaction. Chloroacetyl chloride is also produced by chlorination of acetyl chloride (45—47), the oxidation of 1,1-dichloroethene (48,49), and the addition of chlorine to ketene (50,51). Dichloroacetyl and trichloroacetyl chloride are produced by oxidation of trichloroethylene or tetrachloroethylene, respectively. 

Various catalytic materials promote dehydrochlorination including AlCl (6,91), AICk-nitrohenzene complex (114), activated alumina (3), and FeCl (112). Chlorination in the presence of anhydrous aluminum chloride gives hexachloroethane. Dry pentachloroethane does not corrode iron at temperatures up to 100°C. It is slowly hydrolyzed by water at normal temperatures and oxidized in the presence of light to give trichloroacetyl chloride. 

Trichloroacetanilide has been prepared from hexachloroacetone and aniline, from trichloroacetyl chloride and aniline, by the action of aniline magnesium iodide on ethyl trichloroacetate, by heating N-phenyltrichloroacetimidyl chloride with dilute methanol, and from trichloroacetic acid and aniline in the presence of phosphorus oxychloride. ... 

It is of interest to note that 2,4,6-trinitrochlorobenzene reacts similarly with 49 to give the cation of 138 isolated as the perchlorate. In the reaction of the enamino ketone (50) with trichloroacetyl chloride (77) the chloro-... 

In the reaction with enamino ketones derived from dimedone (e.g., 49) p-toluenesulfonyl chloride gives the chloroiminium cation (138) isolated as the perchlorate. This indicates that initial O sulfonation is followed by addition of chloride ion and subsequent expulsion of tosylate (42) in a manner similar to the trichloroacetyl chloride reaction with 49 (Section IV.A). 

Acylation of the vinylogous pyrrolidine amide of dimedone with acetic anhydride or acetyl chloride led (possibly indirectly) to the carbon acylation product, whereas trichloroacetyl chloride gave rise to products derived from attack of chloride at the oxygenated double bond position in an initial 0-acylation product (401-404). 

Symmetrical piperazines 364 have been obtained from the corresponding 4,5-dihydrazinofurazano[3,4- ]pyraz ne 363 in good yield on reaction with acetic anhydride in the presence of a Lewis acid (Equation 98) <1999CHE499>. When formaldehyde was used, the yield was slightly reduced at 76%. Acid chlorides can also be used in this reaction although the yield drops to 23% when trichloroacetyl chloride is used. 

Trichloroacetyl chloride, 6 269 S-2,3,3-Trichloroallyl diisopropyl-(thiocarbamate), 2 549t... 

Tri-n-butylcarbinol, 52, 22 TRI-tert-BUTYLCYCLOPROPENYL FLUOROBORATE, 54, 97 Trichloroacetyl chloride, with pyrrole to give pyrrol-2-yl trichloromethyl ketone, 51, 100... 

Two further compounds are briefly discussed here. Tetrachloroethylene administered to animals yielded 2,2,2-trichloroacetic acid (10.95, Fig. 10.23) as the only chlorinated metabolite [13]. These findings provided the first evidence that tetrachloroethylene is oxidized by cytochrome P450 to its epoxide (10.94), which rearranges by Cl migration to 2,2,2-trichloroacetyl chloride (Fig. 10.23). The latter hydrolyzes to 2,2,2-trichloroacetic acid (10.95), but also acylates tissue proteins, a reaction of unclear toxicological significance. In vitro investigations of tetrachloroethylene oxide (2,2,3,3-tetrachlo-rooxirane, 10.94) further showed that it hydrolyzes to the vicinal diol (10.96... 

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