338-65-8 l-Chloro-2,2-difluoroethane

Chlorofluorocarbon-blown foam blocks are used to insulate the walls and roofs of some buildings, thus reducing heat losses and helping to conserve fossil fuels. In this area, polyurethane foam competes with polystyrene foam, which until recently was blown with dichlorodifluoromethane (CFC 12) but is now blown with a mixture of chlorodifluoromethane (HCFC 22) and 1 -chloro-l,l-difluoroethane (HCFC 142b). 

Silva, A.M., and L. A. Weber, "Ebulliometric Measurement of the Vapor Pressure of 1-Chloro-l,l-Difluoroethane and 1,1-Difluoro Ethane, J. Chem. Eng. Data, 38, 644-646 (1993). 

Chloro-2-butene l-Chloro-2,3-epoxypropane 1 -Chloro-1,1 -difluoroethane 1 -Chloro-2,4-dinitrobenzene... 

Chloro-l, 1-dilluoroethone (1,1-Difluoro-l -chloroethane) (Genetron-142-B, Trademark of Esso Standard), CH3.CC1F3 mw 100.50 colorless, flammable gas sp gr 1.194 at —9°, fr p —130.8°, bp —9.2° insol in w. Can be prepd by chlorinating 1,1-difluoroethane in UV light. Used as solvent, aerosol proplnt refrigerant also for prepn of fluocarbon plastics... 

With successive equivalents of chlorine monofluoride 1,1 1,2 tetrachloroethane gives l-fluoro-l,l,2-tnchloroethane, 1,2 dichloro-l,l-difluoroethane, 2-chloro 1,1,1-tnfluoroethane with some 1-chloro-l 1,2 tnfluoroethane, and finally 1,1,1,2 tetra-fluoroethane (equation 13)... 

CHLORO-l,l-DIFLUOROETHANE see CFX250 CHLORODIFLUOROETHANES (DOT) see CFX250 CHLORODIFLUOROMETHANE see CFX500 CHLORODIFLUOROMETHANE see CFX500 CHLORODIFLUOROMETHANE (ACGIH,DOT,OSHA) see CFX500... 

Silva and Weber (1993) reported vapor pressure measurements for the 1-chloro-l,l-Difluoroethane (R142b) and 1,1-Difluoroethane (R152a) refrigerants. The data are given in Tables 3.5 and 3.6 respectively. Use Antoine s equation to correlate the data for R142b and the following equation for R152a (Silva and Weber, 1993)... 

DOT Proper Shipping Name l-Chloro-l, 1 difluoroethanes DOT Classification 2.1 (Flammable gas)... 

C2H3CIF2 + C2H3CI2F + 1-Chloro-1,1-difluoroethane + 1,1-Dichloro-l-fluoroethane EVLM 1131 EVLM 1131 LB1138 LB 1943... 

Preparation. Thermal elimination of HCl from l-chloro-l,l-difluoroethane (HCFC-142b) [75-68-3] is the principal industrial route to VDF covered by numerous patents (8—19). Dehydrohalogenation of l-bromo-l,l-difluoroethane (20), or 1,1,1-trifluoroethane (HFC-143a) (21—25), or dehalogenation of l,2-dichloro-l,l-difluoroethane (26—28) are investigated alternative routes (see Fluorine compounds, organic-fluorinated aliphatic compounds). 

Bromo-l-chloro-l,l-difluoroethane (3) is prepared from l,2-dibromo-l,l-dichloroethane (1) in good yield when the fluorination reaction with antimony(III) fluoride/antimony(V) chloride is conducted in two steps. 

Figure 3. Conceptual diagram of an annular photochemical reactor for the production of l-chloro-l,l-difluoroethane in the gas phase with introduction of 1,1-difluoroethane at different levels [2, 3].

Chloro-l.l-difluoroethane (17) eliminates hydrogen chloride on heating with Amberlile IRA 400 to give 1,1-difluoroethene (15).18... 

The reaction of 1-chloro-l-fluoroethane over copper(II) chloride or alumina at 180°C yields 1,1-difluoroethane and 1,1-dichloroethane.32 The conversion is 70% and the yields of both compounds are 40 and 38 %, respectively. This indicates that only minimal hydrogen chloride formation may occur during this disproportionation. 

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