Patent GB-943373-A (GB)
Title: Fluorothiiranes
Inventor: MCGREW FRANK CLIFTON
IPC: C08G75/08
Filed: 1962-05-15
Abstract: The invention comprises fluorothiiranes of formula: <FORM:0943373/C2/1> where A and B are each fluorine, chlorine, perfluoroalkyl, o -chloroperfluoroalkyl, or o -hydroperfluoroalkyl and their preparation by reacting hexafluoropropylene-1, 2-epoxide with a compound A.CS.B at 150-500 DEG C.; CF3COF is also obtained. In examples: (a) A=B=F; (b) A=CF3, B=F; (c) A=Cl, B=F; and (d) A=B=CF3.  In the last case some tetrakis (trifluoromethyl)-1, 3-dithietane is also obtained. Other compounds of the given formula are listed.  Starting materials. Hexafluoropropylene-1, 2-epoxide is obtained from hexafluoropropylene and alkaline aqueous hydrogen peroxide. Compounds ACS.Cl where A is a polyfluoroalkyl radical as defined above are prepared by the vapour phase reaction between ACCl3 and sulphur. Compounds ACS.F are prepared by reacting ACS.Cl with SbF3, or by the reaction of NaF with the mercaptans formed by addition of H2S to polyfluoro-olefines, or by reacting (ACFX)2Hg, where X is H.Cl or F, with molten sulphur or P2S5 at above 400 DEG C. Compounds A.CS.B may be prepared as in U.S.A. Specification 2,970,173.  The lower-boiling compounds of the invention are useful in refrigerant systems, and the higherboiling compounds as fire-extinguishing liquids.  The compounds of invention can be polymerized (see Division C3).  Specification 868,459 also is referred to.ALSO:The invention comprises polymers of compounds: <FORM:0943373/C3/1> where A and B are each fluorine, chlorine, perfluoroalkyl, o -chloroperfluoroalkyl or o -hydroperfluoroalkyl (see Division C2) and their copolymers with other polymerizable monomers the polymers are prepared by subjecting the fluorothiiranes, alone or with other polymerizable monomers, to polymerization conditions under the influence of free radical-producing initiators, such as U.V. light (alone or in conjunction with sensitisers such as benzoin alkyl ethers), nitrogen fluorides such as NF=NF, and acyl peroxides. The polymers contain the repeating unit -CAB-CF2-S-. Other polymerizable monomers which may be copolymerized with the fluorothiiranes include perfluoro-1-alkenes, e.g. C2F4, C3F6 and perfluoro-1-octene; terminal methylene compounds such as propylene, isobutylene, vinyl esters such as the acetate, butyrate, chloride and fluoride; acrylates such as methyl methacrylate and ethyl acrylate; and thiocarbonyl halides such as the fluoride and the chlorofluoride. Examples polymerize tetrafluorothiirane with U.V. light, with N2F4 (with or without a solvent) and with benzoyl peroxide; tetrafluorothiirane and tetrafluoroethylene with N2F4; tetrafluorothiiran and ethyl acrylate with benzoin methyl ether and U.V. light; similarly with vinyl acetate in place of ethyl acrylate; 2,2,3-trifluoro-3-chlorothiirane with N2F4; and tetrafluorothiirane and propylene with N2F4.  The polymers can be used as impregnating agents for porous materials (see Division D1), as coating agents for non-porous surfaces (see Division B2), for packaging and wrapping purposes, as components of waxes and as softeners or plasticizers for high-melting polymers such as polytetrafluoroethylene.  Specification 868,459 is referred to.ALSO:The higher-boiling compounds of formula <FORM:0943373/A5-A6/1> where A and B are each fluorine, chlorine, per. fluoroalkyl, o -chloroperfluoroalkyl or o -hydroperfluoroalkyl (see Division C2) are of use as fire-extinguishing liquids. Specification 868,459 is referred to.ALSO:Polymers containing the repeating unit -CAB-CF2-S-where A and B are each fluorine, chlorine, perfluoroalkyl, o -chloroperfluoroalkyl or o -hydroperfluoroalkyl (see Division C3) are of use as protective coatings for non-porous surfaces such as glass, plastics or metals, e.g. steel, aluminium or copper, imparting water-repellency and resistance to combustion. Specification 868,459 is referred to.ALSO:Polymers containing the repeating unit -CAB-CF2-S-where A and B are each fluorine, chlorine, perfluoroalkyl, o -chloroperfluoroalkyl, or o -hydroperfluoroalkyl (see Division C3) are of use as impregnating agents for porous materials such as paper, cardboard, natural or synthetic fibres or fabrics, wood and brick, imparting water-repellency and resistance to combustion.  Specification 868,459 is referred to.