L-Chloro-2,2,2-trifluoroethyl

Trifluoroethanol is also the starting material for the anesthetic Isoflurane (l-chloro-2,2,2-trifluoroethyl difluoromethyl ether [26675-46-7]) (55,56) and Desflurane (2-difluoromethoxy-l,l,l,2-tetrafluoroethane [57041-67-5]) (57). 

Reaction of 2-cyanomethylpyridine with iV-(l-aryl-l-chloro-2,2,2-trifluoroethyl)-iV -(4-methylphenyl)carbodiimides, and with (1,1,2,2,2-pentachloro- and l,l-dichloro-2,2,2-trifluoroethyl)isocyanates or A-methoxycarbonyl-l,2,2,2-tetrachloro-, — l-chloro-2,2-trifluoroacetaldehyde imines afforded 3-aryl-4-cyano-l-(4-methylphenyl)imino-3-trifluoromethyl-2,3-dihydro-17/-pyrido[l,2-f]pyrimidines and 4-cyano-3-trichloro-, 4-cyano-3-trifluoro-17/-pyrido[l,2-4pyrimidin-l-ones, respectively <2004CHE47>. Refluxing 2-cyanomethylpyridine and iV-(l-aryl-l-chloro-2,2,2-trifluoroethyl)isocyanates in benzene furnished l-aryl-4-cyano-l-trifluoromethyl-l,2-dihydro-3//-pyrido[l,2-4pyrimidin-3-ones. However, when the solution of the isocyanate was added dropwise to the solution of 2-cyanomethylpyridine, and the reaction mixture was then treated with NEt at room temperature, the isomeric 3-aryl-4-cyano-3-trifluoromethyl-2,3-dihydro-l//-pyr-ido[l,2-dpyrimidin-l-ones were obtained. Reaction of l-(acetyl- and benzoylmethylene)-6,7-dimethoxy-l,2,3,4-tetra-hydroisoquinolines with PhCONCS yielded 1-acetyl-, 1 -benzoyl-9,10-dime thoxy-3-pheny 1-6,7-dihydro-2//-pyrimido[6,l- ]isoquinoline-2-thiones <2003SL2369>. 

In the preceding eqnation, the primary anion-radical gives the l-chloro-2,2,2-trifluoroethyl radical. In vivo, this radical was detected by the spin-trapping method (Poyer et al. 1981). Ahr et al. (1982) had presented additional evidence for the formation of the radical as an intermediate in halo-thane metabolism and identified l-chloro-2,2-difluoroethene as a product of radical stabilization. Metabolytic transformations of l-chloro-2,2-difluoroethene lead to acyl halides, which are relevant to halothane biotoxicity (Guengerich and Macdonald 1993). 

In the thermal cyclization of 3-alkoxyphenyl A -(l-aryl-2,2,2-trifluoroethylidene)carbamates 287, obtained from 3-alkoxyphenols 285 and l-aryl-l-chloro-2,2,2-trifluoroethyl isocyanates 286, 2-aryl-2-trifluoromethyl-2,3-dihydro-477-l,3-benzoxazin-4-ones 290 were formed instead of the regioisomeric l,3-benzoxazin-2-ones 288 (Scheme 53). The formation of 290 was explained by a thermal isomerization of 287 involving a skeletal 1,3-rearrangement of the electron-rich aryloxy group to the azomethine carbon, which is electron deficient due to the electron-withdrawing CF3 group <2002JFC(116)97>. 

Many ethers, including diethyl ether, are effective as general anesthetics. Because simple ethers are quite flammable, their place in medical practice has been taken by highly halogenated nonflammable ethers. Two such general anesthetic agents are isoflurane and enflurane. These compounds are isomeric isoflurane is l-chloro-2,2,2-trifluoroethyl difluoromethyl ether enflurane is 2-chloro-l,l,2-trifluoroethyl difluoromethyl ether. Write the structural formulas of isoflurane and enflurane. 

Chemical Name l-Chloro-2,2,2-trifluoroethyl difluoromethyl ether... 

Phenyl(l-bronio-l-chloro-2,2,2-trifluoroethyl)mercury, C HsHgCClBrCFj. Mol. wt. 474.14, m.p. 140-144°. 

Acetone, l-chloro-2,2, 2-trifluoroethyl-chlorodifluoro-methyl ether 2,2,2-trifluorethyl-difluormethyl ether... 

The thermal decomposition of l-bromo-l-chloro-2,2,2-trifluoroethyl(phenyl)mercury at 130-140 °C in the presence of an alkene afforded 1-chloro-l-trifluoromethylcyclopropanes 28 (see Houben-Weyl, Vol. E19b, pp 1036-1037). 

In conditions of low levels of oxygen, a reductive pathway (10%) is enhanced and yields a free radical intermediate characterized as l-chloro-2,2,2-trifluoroethyl radical. Another one-electron rednction produces the l-chloro-2,2,2-trifluoroethyl carbanion, which may undergo two possible kinds of eliminations. 

The initially formed l-chloro-2,2,2-trifluoroethyl radical may also canse a radical attack of polyunsaturated lipids, which produces l-chloro-2,2,2-trifluoroethane. This mechanism is similar to the pathway described with the trichlo-romethyl radical formed during the one-electron reduction of carbon tetrachloride (Eigure 33.14). The trichloromethyl radical may initiate a peroxidation of unsaturated lipids from the membrane with subsequent liberation of chloroform. 

Vovk MV, Lebed PS, Chemega AN, Pirozhenko VV (2004) Unusual cyclization of N-(l-Aryl-l-chloro-2,2,2-trifluoroethyl)-N -(p-tolyl)-carbodiimides in the presence of trieth-ylamine. Russ J Org Chem 40 195-198... 

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