A method for preparing (R)X.sub.m-p A.sub.p by reacting (R)X.sub.m and MA in N-methylpyrrolidone and recovering the by-product MX as a precipitate wherein:X is halide;R contains from 1 to 8 carbon atoms, can be substituted or unsubstituted, and is straight or branched chain alkyl, cycloaliphatic, aralkyl, alkylene, alkenyl, alkenylene, alkynyl or alkynylene with the proviso that X is not attached to a carbon atom having a double bond;A.sup.- is a monovalent anion soft base selected from the group consisting of halide different from X, SCN.sup.-, SH.sup.-, SO.sub.3 H.sup.-, R.sub.2 PO.sub.4.sup.-, PF.sub.6.sup.-, and [SP(Z) (OR.sup.1).sub.2 ].sup.- wherein R.sup.1 is lower alkyl and z i sulfur or oxygen;M is an alkali metal or NH.sub.4.sup.+ ;m is an integer from 1 to 3 with the proviso that m is 1 or 2 when R has one carton; andP is an integer from 1 to m.