GB701794A - Improvements in and relating to halogen containing organic compounds of phosphorus - Google Patents

Abstract

Organic phosphates or organic phosphonates containing one or more halogen substituted alkyl groups connected with the phosphorus atom through an oxygen atom are produced by a process which comprises reacting at a temperature between 20 DEG C. and 100 DEG C., in the presence of a halide of titanium or zirconium as catalyst a phosphorus compound as defined below with an oxirane compound having the formula <FORM:0701794/IV(b)/1> wherein R is a hydrogen atom or an alkyl, or a chlorine- or bromine-substituted alkyl radical. The term phosphorus compound refers to phosphoryl chloride, the chloride-bromides and the bromide; mono- and dialkyl chlorophosphates and bromo-phosphates such as dibutyl chlorophosphate, mono-butyl dichlorophosphate, di-(2-ethyl-hexyl) chlorophosphate and di-(dodecyl) chlorophosphate; the cycloalkyl chloro- and bromophosphates such as di-cyclo-hexyl chlorophosphate; the aryl and alkaryl chlorophosphates such as diphenyl-chlorophosphate, phenyl dibromo - phosphate, p-tertiary-butylphenyl dichloro-phosphate and cresyl dichlorophosphate; halogenated alkyl and aryl chlorophosphates such as 2-chloro-ethyl dichlorophosphate, di(2-chloroethyl) chloro-phosphate, 2-bromoethyl dibromo-phosphate, p-chlorophenyl dichlorophosphate, di-(p-chlorophenyl) chlorophosphate; amidophosphoryl halides and alkyl- and aryl-substituted amidophosphoryl halides such as amidophosphoryl dichloride, N:N-diethylamido-phosphoryl dichloride, N:N-dibutylamidophosphoryl dichloride, N:N-diphenyl-amidophosphoryl dichloride and N:N1-diethyl-diamido-phosphoryl chloride; alkoxyalkyl, polyalkoxyalkyl, aryloxyalkyl and aryloxy-polyalkoxy-alkyl halogenated phosphates such as methoxyethyl, methoxyethoxyethyl, ethoxyethyl, butoxyethyl, phenoxyethyl and phenoxyethoxyethyl mono- and di-chloro-phosphates; and the corresponding derivatives of the bromo-phosphates and the alkyl- and aryl-substituted phosphonyl halides such as methane-phosphonyl dichloride, ethane-phosphonyl dichloride and benzenephosphonyl dichloride. The alkoxy-alkyl, polyalkoxyalkyl aryloxyalkyl and aryloxypolyalkoxyalkyl halogenated phosphates may be prepared by reacting a substituted alcohol containing one of the said groups with phosphorus oxychloride at a temperature of about 15 DEG C. according to the equation: <FORM:0701794/IV(b)/2> where R is alkyl containing one of the said groups. Oxirane starting materials mentioned include ethylene oxide, a -propylene oxide, isopropyl ethylene oxide, 1:2-butylene oxide, epichlorohydrin and epibromohydrin. The preferred catalysts are the tetrachlorides and tetrabromides of titanium and zirconium though oxides and those other compounds, e.g. titanium potassium oxalate, of these metals capable of forming the halides of these metals in phosphoryl halide or in the substituted halide and zirconium oxychloride may be employed. In examples: Tri-(2-chloroethyl) phosphate is prepared by reacting ethylene oxide and phosphoryl chloride using as catalysts titanium tetrachloride (1, 2), zirconium tetra-chloride (4), titanium tetrabromide (5) and zirconium oxychloride (8); tri-(dichloro propyl) phosphate is prepared from epi-chlorohydrin and phosphoryl chloride using titanium tetrachloride as catalyst (3); tri-(2-chloropropyl) phosphate is prepared from phosphoryl chloride and propylene oxide with titanium tetrachloride as catalyst (6); 2-bromoethyl dibutyl phosphate is prepared by reacting dibutyl bromophosphate prepared by reacting tributyl phosphite with bromine, with ethylene oxide in the presence of titanium tetrachloride (9); p-nonylphenyl di-(2-chloroethyl) phosphate, di-(2-chloroethyl) N-(2-ethylhexylamido)-phosphate, di-(2-chloroethyl) N:N-diethylamido - phosphate and di-(2-chloroethyl) benzene - phosphonate are prepared by reacting in the presence of titanium tetrachloride with ethylene oxide, p-nonylphenyl dichlorophosphate (7), N-2-ethylhexylamidophosphoryl dichloride (10), N:N - diethylamidophosphoryl dichloride (11), and benzene phosphonyl chloride (12) respectively; The desired products are recovered by neutralizing the reaction product with an aqueous slurry of calcium or barium carbonate, filtering the mixture and fractionating the filtrate or by agitating with an aqueous solution of trisodium citrate, disodium tartrate or potassium tartrate to form a water soluble complex with the catalyst which is washed out with water and distilling the washed product under vacuum. The reaction mixture itself may be fractionated. Other products obtained using titanium tetrachloride as catalyst are n-butyl di-(2-chloroethyl phosphate), cresyl di-(2-chloro-ethyl) phosphate, di-(2-chloroethyl) 2-methoxy-ethyl phosphate, p-chlorophenyl di-(2-chloroethyl) phosphate, p-tertiary butylphenyl di-(2-chloro-ethyl) phosphate, di-(2-chloroethyl) 2-phenylethyl phosphate, 2-chloroethyl diphenyl phosphate, di-(dichloropropyl) phenyl phosphate, di (2-chloroethyl) phenyl phosphate, di-(2-chloroethyl) N-butyl-amido-phosphate, 2-chloroethyl di (chloropropyl) phosphate and 2-chloroethyl di (2:3-dichloropropyl) phosphate. The halogen-substituted alkyl phosphates and phosphonates are plasticizers for thermoplastic resins and impart flame-proofing properties to compositions. The catalysis of the reaction between phosphorus oxychloride and ethylene oxide by aluminium chloride, aluminium bromide and mixtures of mono- and dialkyl aluminium bromides and iodides, ferric chloride, iron fillings and boron tetrafluoride is referred to. Alkoxyalkyl, polyalkoxyalkyl, aryloxyalkyl and aryloxypolyoxyalkyl halogenated phosphates may be prepared by reacting a substituted alcohol containing one of the said groups with phosphorus oxychloride.