2-Chloro-l,1,1-trifluoroethane

Brome-2-chloro-l, 1,1-trifluoroethane Ethane, 2-bromo-2-chloro-l, 1, l-trifluoro- B.P., U.S.P.,... 

Haloalkanes can be regarded as substituted alkanes in which one or more of the hydrogen atoms is replaced by a halogen atom. They are named in a similar fashion to branched-chain alkanes with the halogen atoms treated like branches. For example, the anaesthetic halothane has the structure shown in the diagram and is called 2-bromo-2-chloro-l,l, 1-trifluoroethane. 

Disposition in the Body. Rapidly absorbed upon inhalation blood gas partition coefficient about 2.4. It accumulates in adipose tissue. About 60 to 80% of an absorbed dose is exhaled unchanged from the lungs in 24 hours and smaller amounts continue to be exhaled for several days or weeks. A variable amount is metabolised in the liver by debromination and dechlorination replacement of a fluorine atom by a methoxy group followed by glucuronic acid conjugation occurs to a limited extent. Other metabolites which have been detected in expired air and in blood are 2-chloro-1,1,1-trifluoroethane and 2-chloro-l, 1-difluoroethylene. Up to about 20% of a dose may be excreted in the urine as trifluoroacetic acid and its salts. Bromide ion is slowly excreted in the urine. 

The aminolysis of fluorinated compounds such as 2-chloro-l,1,l-trifluoroethane (4)8 or the tosylate 6,9 to give amines 5 and 7, respectively, is achieved only under severe reaction conditions. 

Halothane (2-Bromo-2-chloro-1,1,1 -trifluoroethane) (HCBD) see Hexachloro-1,3-butadiene (HCFC-141B) see 1,1-Dichloro-l-fluoroethane (HDDA) see 1,6-Hexanediol diacrylate (HEMA) see 2-Hydroxyethyl methacrylate n-Heptane... 

Trifluoroethanol was first prepared by the catalytic reduction of trifluoroacetic anhydride [407-25-0] (58). Other methods iaclude the catalytic hydrogeaatioa of trifluoroacetamide [354-38-1] (59), the lithium aluminum hydride reductioa of trifluoroacetyl chloride [354-32-5] (60) or of trifluoroacetic acid or its esters (61,62), and the acetolysis of 2-chloro-l,l,l-trifluoroethane [75-88-7] followed by hydrolysis (60). More recently, the hydrogenation of... 

Difluoromethoxy-2-chloro-l,l,l-trifluoroethane and potassium fluoride produce 2-difluoromethoxy-1,1,1,2-tetrafluoroethane [50] The yield of the latter reaction is improved by adding a phase transfer catalyst or crown ether, tetra-methylammonium chlonde, tetrabutylammonium chloride, or 18-crown-6 with a solvent like sulfolane can be used for this purpose [5/] (equation 32)... 

A nonconventional synthesis of the known inhalation anaesthetic, 2-bromo-2 chloro-l,l,l-trifluoroethane (Halothane), based on the reaction of ethyl 1,2 di bromo-1,2-dicliloroethyl ether with anhydrous hydrogen fluoride and sulfur tetrafluoride, has been patented The reaction presumably involves cleavage of the ether linkage, followed by fluorination of the intermediate bromochloroacetyl halide with sulfur tetrafluoride, ethyl halides are the by-products [2] (equation 2)... 

Complex formation equilibria in binary mixtures of chloroform with dipropyl ether (PE), diisopropyl ether (IPE), methyl tert-butyl ether(MBE), tetrahydrofuran (THE), 1,4-dioxane (DOX), acetone (AC), and methyl acetate (MA) have been analyzed in detail. The complex formation equilibria in chloroform mixtures was compared to those previously examined for halothane (2-bromo-2-chloro-l,l,l-trifluoroethane) mixed with the same oxygenated solvents. It was found that the H-bonds formed by halothane are stronger than those formed by chloroform (Dohnal and Costas, 1996). 

In addition to MAK values, which are for healthy persons capable of earning a normal living, the DFG publication20 includes so-called BAT values (biological tolerance limits) for substances which show additional biological effects. These define maximum concentrations of a substance, or its metabolites, normally in the blood or urine of an employee. Only one fluorinated chemical was included in 1997. 2-bromo-2-chloro-l,l,l-trifluoroethane = Halo-thane, CAS-No. 151-67-7, with a BAT value for trifluoroacetic acid (its toxic metabolite) of 25 mg - L 1 in human blood determined after exposure/shift. 

A series of halogenated ethanes 1 containing the trifluoromethyl group has been oxidized under various conditions.5-7 When water is present in the reaction mixture, the acid 3 is usually formed during the reaction when water is absent, the acid halide 2 formed can be hydrolyzed in a trap with water. Trifluoroacetaldehyde hydrate 4 is formed6 as a minor product in addition to the acid when 2-chloro-l,l,l-trifluoroethane is treated with oxygen and chlorine under UV irradiation with subsequent reflux of the mixture with hydrogen peroxide. 

As 2-chloro-l,l,l-trifluoroethane (HCFC-133b) and 2,2-dichIoro-l,l,l-trifluoroethane (HCFC-123b) are industrially produced CFC alternatives, the original academic oxidative reaction to produce them is now of technical importance 7 a thermal oxidation method for 2.2-dichloro-l,1,l-trifluoroethane that is attractive from an industrial point of view has been developed7 and high yields of trifluoroacetic acid were obtained in a continuous process in addition, minor products were characterized. The acid is formed by continuous hydrolysis of the reaction mixture.7... 

Bromo-2-chloro-l.l,l-trifluoroethane (3) is obtained from 1.2-dibromo-1.2-dichloro-l-ethoxyethane with sulfur tetrafluoride/hydrogen fluoride at 100 C in an autoclave. ... 

SYNS CFG 133a l-CHLORO-2.2,2-TRIFLUORO-ETHANE 2-CHLORO-l,l,l-TRIFLUOROETHANE FC 133a FREON 133a GENETRON 133a R 133a 1,1,1-TRIFLUORO-2-CHLOROETHANE 1,1,1-TRIFLUORO-ETHYL CHLORIDE... 

CHLORO-l,l,l-TRIFLUOROETHANE see pY175 2-CHLORO-1,1,2-TRIFLUOROETHYL DIFLUOROMETHYL ETHER see EAT900 CHLOROTRIFLUOROETHYLENE see CLQ750... 

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