A new preparation of W(CO)₅(PH₃) (1) in fair yield on a multigram scale has been devised. 1 is metalated by one equivalent of n-BuLi to give W(CO)₅ (PH₂Li) (2), which reacts with various electrophiles: with alkyl halides W(CO)₅(PH₂R) complexes are obtained, but with other electrophiles the species W(CO)₅(PHR₂) is also obtained along with 1. Disubstituted complexes can also be obtained when 1 is treated with an excess of n-BuLi followed by an excess of an electrophile. The results are rationalized by postulating that polysubstituted compounds are obtained by stepwise deprotonation of less-substituted complexes rather than via polylithiated complexes such as W(CO)₅(RPLi₂) or W(CO)₅(PL₃). A one-pot preparation of W(CO)₅[P(SiMe₃)₃] in good yield from 1 was also achieved. The intermediate W(CO)₅[LiP(SiMe₃)₂] was also made from 1, and its reaction with BrCH₂Cl followed by hydrolysis gave (CO)₅W(PH₂CH₂PH₂)W(CO)₅.