Patent GB-675279-A (GB)
Title: Improvements in preparing polyhalogenoalkenyl compounds
IPC: C07C43/14
Filed: 1949-02-17
Abstract: Dichloro-alkenyls of formula Cl2C=CR-CR1-R11-A, where R, R1 and R11 are H or hydrocarbon radicles, are made by heating a tetra-halogenoalkane (halogen excluding fluorine and iodine) containing a trihalogenomethyl group in which two of the halogens are chlorine and the third is bromine or chlorine connected to an additional halogen atom by an aliphatic chain of two carbon atoms, with an alkaline substance MA, where M is hydrogen, an alkali or alkaline earth metal ion or the ammonium ion and A is an acidyloxy, alkoxy, alkenylalkoxy, aryloxy, aralkoxy or amino radicle. Occasionally compounds X3C-CR=CR1R11 may also be formed.  Many of the said groupings for A are specified, representative being:-acetoxy, chloracetoxy, phenacetoxy, acryloxy, lauroyloxy, benzoyloxy, adipyloxy, propoxy, cyclopentoxy, dodecoxy, crotyloxy, chloroallyloxy, geranyloxy, tolyloxy, p-chloro- and p-methoxy-phenoxy, and beta-phenylethoxy. Many hydrocarbon radicles are specified for the R's including R as methyl and phenyl and R1 and R11 as isopropyl, cyclopentyl, decyl, 3-butenyl, 4-cyclohexenyl, tolyl, naphthyl and benzyl and R and R11 may constitute an aliphatic chain of 3 or 4 carbon atoms, e.g. tetramethylene.  At least one of R, R1 and R11 is preferably H and R is H when R1 and R11 are H. Preferred aspects relate to the preparation of Cl2C=CH-CR1R11-A, Cl2C=CH-CHR11\h -A and Cl2C=CHCH2A.  A table of reactions is provided, representative of many specified being Cl3CCH2CH2Cl + NaOCOPh --> Cl2C= CHCH2OCOPh; Cl3CCH2CH2Br + KOH + CH3OH --> Cl2C=CHCH2OCH3; Cl2BrCCH2 CH2Br+NH3 --> Cl2C=CHCH2NH2+corresponding sec. and tert. amines and Cl2CCH2 CH2Cl + KOCH2CH = CH2 --> Cl2C = CH-CH2OCH2CH = CH2. Specified temperatures are 25-200 DEG  C. Preferably 1-4 mols. of alkaline reagent are used.  Times range from 0.1 to 48 hours. Diluents may be present.  Pressure may be used.  In examples 1,1,1,3-tetrachloropropane is reacted with (1) sodium p-chlorophenoxide in ethanol; (2) potassium acetate; and (3) ammonia in aqueous ethanol to produce p-chlorophenyl 3,3-dichloro-2-propenyl ether, 3,3-dichloro-2-propenyl acetate and 3,3 - dichloro - 2 - propenylamine hydrochloride respectively.  The starting materials X3CCHRCR1R11Y are made by the free radicle catalyzed reaction of RHC=CR1R11 with a tetrahalogenomethane CX3Y.  In the Specification as open to inspection under Sect. 91 the R's may have other values including R as carboxyl and carboxymethyl and groups hydrolysable thereto and R1 and R11 as o, p-dichlorophenyl, p-methoxyphenyl, acid and acid-alkyl groups and groups hydrolysable thereto, including carbonitrilo, diethoxyphosphenyl, ethoxy-sulphonyl and trimethoxysilicyl groups, acidoxy and acidoxyalkyl groups and R11 as ether, thioether or heterocyclic groups.  Many of the members of the above classes are specified.  A also has other values, including methyl-sulphate, diethyl-borato, ethylcarbonate, diethylphosphate, and trimethylsilicate, thioether, thioacid ester, disulphite, xanthogeno, thiocyanyl, dithiocarbamyl, fluorine, nitro, imido, hydrazino, substituted amino, carbonitrilo and groups derived from compounds containing an acidic hydrogen, e.g. fluorene, acetylenes and R2-CHR3-COR4, where R2 is acyl, R3 is H or alkyl and R4 is alkoxy, alkyl or aryl.  It is also stated that compounds of formula X2C= CH-CR1R11A may be made in a similar way.  This subject-matter does not appear in the Specification as accepted.