Patent GB-692633-A (GB)
Title: Process for the production of esters of orthophosphoric acid
IPC: C07F9/09
Filed: 1950-10-11
Abstract: Esters of orthophosphoric acid are obtained by reacting organic hydroxyl compounds or cyclic ethers with phosphorus oxychloride, the reaction being carried out in the presence of phosphorus trichloride. The hydroxyl compounds may be aliphatic, aromatic or cyclic alcohols and especially primary or secondary aliphatic and alicyclic alcohols having at least 6 carbon atoms.  Suitable cyclic ethers are alkylene oxides, e.g. ethylene oxide, propylene oxide; and tetrahydrofuran, and mono and dianhydrohexitols, of which the free hydroxyl groups are substituted for example esterified.  In the production of phosphoric acid monoesters the phosphorus chlorides are conveniently used as a whole in excess and can be recovered by distillation or with the aid of water. The phosphorus trichloride may be added to the organic compound before adding the oxychloride or it may be mixed with the oxychloride or added subsequently, or it may be mixed with the oxychloride and its proportion subsequently increased.  Mono-, di-, or triesters can be produced by the process and when mixtures of hydroxy compounds such as are obtained by the catalytic hydrogenation of natural fats are used mixed esters can be produced.  In examples: (1) an alcohol of mean chain length C12 produced from the corresponding olefine by the Oxo synthesis is dissolved in benzene and a mixture of phosphorus oxychloride with 2 per cent by weight of the trichloride is slowly poured in.  The mixture is then refluxed, the excess phosphorus chlorides removed by distillation, and the remaining mass stirred into caustic soda solution.  A white product soluble in water to a neutral reaction is separated from the sodium chloride-containing liquor; (2) phosphorus trichloride is added to octadecyl alcohol dissolved in benzene or other inert solvent, e.g. trichloroethylene and phosphorus oxychloride added slowly. The solution is then refluxed, the acid phosphoric acid ester being obtained; (3) an acid phosphoric acid ester is obtained by heating an alkyl phenol (molecular weight 210) with a mixture of phosphorus oxychloride and a small amount of the trichloride and finally stirring in water or blowing steam into the mixture; (4) a polyoxyethylated phenol (mean molecular weight 640) is reacted with a mixture of phosphorus oxychloride and trichloride at 100 DEG  C. and the reaction product neutralized with caustic soda solution; (5) a mixture of a polyglycol (mean molecular weight 450) and octadecyl alcohol dissolved in trichloroethylene is mixed with phosphorus oxychloride, phosphorus trichloride then added, and the mixture refluxed.  After partial saponification by blowing out with water vapour an acid, readily foaming product is obtained; (6) ethylene oxide is reacted with a mixture of phosphorus oxychloride and trichloride, di-(betachloroethyl) phosphoryl chloride being obtained which is suitable for further reactions, e.g. with sodium nitrophenate or sodium chlorophenate for the production of insecticidal and fungicidal substances; (7) ethylene oxide is reacted with the reaction mixture of example 6 until no more is absorbed, tri-(betachloroethyl) phosphate being obtained.  German Specifications 575,660 and 619,019 and U.S.A. Specification 2,005,619 are referred to.