Novel phosphonium and imidazolium salts and methods for preparing them are disclosed. The novel phosphonium and imidazolium compounds are useful as polar solvents and have the general formula (I): Q.sup.+X.sup.- wherein Q.sup.+ is formula (a) or formula (b); and X.sup.- is formula (c), formula (d) or formula (e); and wherein: each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.9, R.sup.10, R.sup.11, R.sup.12, and R.sup.13 is independently a hydrocarbyl group; each of R.sup.6, R.sup.7, and R.sup.8 is independently a hydrogen or hydrocarbyl group. ##STR00001##