1304627 Flame retardant phosphorus esters; chlorohydroxy compounds MOBIL OIL CORP 6 May 1970 [19 May 1969 18 Sept 1969] 21787/70 Addition to 1303287 Headings C2C and C2P [Also in Division C3] The invention comprises compounds of the Formula I or II where X is chlorine or bromine, or combinations thereof, R is hydrogen, -CH 3 or -CH 2 X, provided that when one R is -CH 3 or -CH 2 X, the adjacent R is hydrogen, R<SP>1</SP> is X, alkyl, haloalkyl, alkoxy, aryl, haloaryl, or arylalkyl, halo being X, R<SP>11</SP> is H or -CH 3 , Q is alkyl, alkoxy, haloaryloxyalkyl or haloarylpoly(oxyalkyl) where halo is X, a is 0, 1 or 2, n is 1, 2 or 3, v is 0 or 1, w is 1, 2 or 3, x is 0 or 1, y is 0, 1 or 2, z is 1 or 2 and x+y+z is 3. The compounds of Formulµ I and II which may be used as flame retardants for polymeric materials may be prepared by reacting an appropriate hydroxyl compound or mixture of hydroxyl compounds with a phosphorus compound, such as a phosphorus trihalide or oxyhalide. Any unreacted halogen atoms attached to phosphorus may be reacted with an alkylene oxide or further hydroxy compound. The phosphites may be converted to phosphates by oxidation or to phosphonates by heating in the presence of a catalyst. The intermediate bis(2-bromoethyl)phosphorochloridate may be prepared by reacting a mixture of tetrabromo (Bisphenol-A) and 2-bromoethanol with phosphorus oxychloride, and may be converted to a compound of Formula II by reaction with the tetrabromo(Bisphenol-A) under alkaline conditions. The mixture of hydroxy compounds used as starting material may be prepared by reacting Bisphenol-A, ethylene oxide and bromine. The corresponding chlorine-containing product and intermediates may be prepared by using chlorine instead of bromine. The intermediate 2,4-dichlorophenoxyethyl phosphorodichloridite may be prepared by reacting 2,4-dichlorophenoxyethanol with phosphorus trichloride, and may be converted to a compound of Formula I by reaction with propylene oxide. A mixture of 2-(2,4-dichlorophenoxy)ethanol and 2-chloroethanol may be prepared by reacting a mixture of 2,4-dichlorophenol and 2-chloroethanol with ethylene oxide, and may subsequently be reacted with phosphorus trichloride to give a compound of Formula I. The mixture of hydroxyl compounds used as starting material may be prepared by reacting phenol. ethylene oxide and chlorine.