Reaction of halothane with carbonyl compounds in the presence of bases

1-Bromo-1-chloro-2,2,2-trifluoroethane (Halothane) as a building block for fluorine compounds

“…This reactions proceeded with both ketones and aldehydes with high selectivity and gave better yields than those of the corresponding Grignard reactions [17]. The reaction of halothane with an excess of secondary butyllithium and zinc chloride in THF at À60 8C gave a clear solution, the 19 F NMR spectra of which suggested that it contained bis(1-chloro-2,2-difluorovinyl)zinc (19).…”

“…Saturated secondary and tertiary 1-(1-bromo-1-chloro-2,2,2-trifluoroethyl) alcohols (6) and (10) were obtained selectively and in high yields (up to 96%) when, instead of LDA, lithium or sodium hexamethyldisilazide (Li/NaHMDS) was used as a base for the reactions of halothane with carbonyl compounds [17].…”

Polyfluorinated Ethanes as Versatile Fluorinated C2-Building Blocks for Organic Synthesis

“…Metalation of Halothane with lithium and sodium hexamethyldisilazide followed by the reaction with carbonyls gave the corresponding alcohols 263 bearing CF 3 CClBr fragment. Contrary, the reaction with butyl lithium gave the products of 1,1-difluoro-2-chlorovinylation 246h through the formation of 1,1-difluoro-2-chlorovinyl lithium and subsequent addition to the carbonyl group (Scheme ) …”

Synthesis of aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers through the base-mediated reaction between phenols and halothane

“…A further example for the formation of an aryl fluoroalkyl ether was the reaction of phenol with 2-chloro-1,1,1-trifluoroethane, also known as HCFC-133a, in the presence of potassium hydroxide (KOH) to give the gemdifluoromethyl ethers along with the formation of 1-fluoro-2chlorovinyl ether (route (d), Scheme 1) [41]. On the basis of our previous reports, we focused on halothane, 2-bromo-2-chloro-1,1,1-trifluoroethane, because the treatment of this compound with several bases was found to provide the highly electrophilic 2-bromo-2-chloro-1,1-difluoroethene [42,43]. Additionally, another report discussed the carbocationic character of the gemdifluorovinyl carbon that was explained by an orbital interaction between the n orbital (fluorine) and the π orbital [44].…”