The invention is an improved method for the preparation of tertiary phosphines by way of cross-coupling of aryl, alkenyl, cycloalkenyl or aralkyl halides or aryl, alkenyl, cycloalkenyl or aralkyl sulfonate esters with chlorophosphines in the presence of a catalyst and a reductant. The general reaction scheme is shown below: ##STR1## wherein R.sup.1 is aryl, alkenyl, cycloalkenyl or aralkyl, any of which may be substituted by one or more of the following: alkyl, aryl, aralkyl, alkoxy, alkanoyl, chloro, fluoro, alkoxycarbonyl, cyano, trifluoromethyl, cycloalkyl, or CONR.sup.4 R.sup.5 wherein R.sup.4 and R.sup.5 are independently hydrogen, alkyl, aryl or aralkyl; R.sup.2 and R.sup.3 are independently aryl, alkyl, aralkyl, any of which may be substituted by one or more of the following: alkyl, aryl, aralkyl, alkoxy, alkanoyl, chloro, fluoro, alkoxycarbonyl, cyano, trifluoromethyl, cycloalkyl or CoNR.sup.4 R.sup.5 wherein R.sup.4 and R.sup.5 are independently hydrogen, alkyl, aryl or aralkyl; and n is 2 where R.sup.1 is a difunctional moiety and 1 for any other R.sup.1 ; and X is Cl, Br, I, or OSO.sub.2 Y; wherein Y is alkyl, trihalomethyl, phenyl, halophenyl, or alkylphenyl.