VERFAHREN ZUR HERSTELLUNG VON ALKYL- ODER ARYLTHIOPHOSPHORHALOGENIDEN UND GEMISCHTEN ISOMEREN DERSELBEN

Improved yields and a lower accumulation of by-product is obtained in the method for preparing compounds of the formula: wherein R is a C1 to C20 alkyl radical, cycloalkyl of 5-6 carbon atoms in the ring and the C1-C4 alkyl substituted derivative thereof, an aralkyl radical of up to two fused rings, the alkyl portion having from 1 to 20 carbon atoms, an aryl radical of up to three fused rings and the C1-C4 alkyl derivatives thereof, and biphenyl and the C1-C4 alkyl derivatives thereof, X is a halogen of chlorine or bromine, and Z is either R or X, by the reaction of a phosphorus halide source, a hydrocarbon source selected from the group consisting of RH, RX and RSaR, wherein a is 1 or 2 and a sulfur source under autogenous pressure in an autoclave at a temperature ranging from about 175 DEG C. to about 450 DEG C. by recycling to successive runs a by-product of the reaction remaining after separation of the RP(S)XZ product fraction selected from the group consisting of: