The title compound, C21H22P+. BCl4-, is the first structurally characterize
d example of the [HP(o-tolyl)(3)](+) cation, presented here with BCl4- as t
he counter-ion. The cation has a near-tetrahedral P atom and the BCl4- anio
n is near-tetrahedral at boron. There are no unusually short cation-anion c
ontacts.