The reaction of the anilines RNH2 [R = C6H4(o-CN), C6H4(p-CN), C6H4(m-CN), C6H4(o-C6H5), C6F5 and C6H4(o-CF3)] with Ph2PCl and inorganic or organic bases in differing stoichiometry and in different solvents has been studied. The electronic properties and steric effects of the substituent groups, the base employed, the stoichiometry and the solvent all influence the outcome of the reaction and a series of aminophosphines, diphosphinoamines and iminobiphosphines have been isolated and characterised. The structures of three diphosphinoamines and three iminobiphosphines have been established using single-crystal X-ray diffraction.