Process for preparation of aromatic phosphorus compounds

Claim 1

IN A PROCESS FOR PREPARING AN ORGANIC PHOSPHORUS COMPOUND OF THE FORMULA RXP(OR'')(3-X) WHEREIN R IS AN ALKYL OR ARYL RADICAL OF 1 TO 18 CARBON ATOMS, R7 IS AN ARYL RADICAL OF 6-25 CARBON ATOMS AND X HAS A VALUE OF 0-2 BY MAINTAINING A REACTION MIXTURE COMORISING A PHENOL AND A PHOSPHORUS HALIDE OF THE FORMULA RXPX(3 X), WHEREIN X IS A HALIDE OF THE GROUP CONSISTING OF CHLORIDE, BROMIDE AND IODIDE, AND R AND X ARE AS DEFINED ABOVE, AT A TEMPERATURE IN THE RANGE OF ABOUT 25*C. TO THE BOILING POINT OF THE RESULTING ORGANIC PHOSPHORUS COMPOUND; THE IMPROVEMENT WHICH COMPRISES INCORPORATING INTO THE REACTION MIXTURE WHEN REACTION OF THE PHENOL WITH THE PHOSPHORUS HALIDE IS SUBSTANTIALLY COMPLETE AT LEAST A STOICHIOMETRIC AMOUNT BASED ON THE RESULTANT HYDROGEN HALIDE IN THE REACTION MIXTURE OF A METAL SELECTED FROM THE CLASS CONSISTING OF ZINC, CHROMIUM, TITANIUM, CADMIUM AND MIXTURES THEREOF AND MAINTAINING THE REACTION MIXTURE AT A TEMPERATURE IN THE RANGE OF 25*C. TO THE BOILING POINT OF THE REACTION MEDIUM FOR FROM 0.1 TO 2 HOURS TO PRODUCE AN ORGANIC PHOSPHORUS COMPOUND FREE OF HYDROGEN HALIDE.