The 1:1 and 2:1 reactions of (Me3Si)(2)PLi . 2THF with several amino chlorophosphanes have been surveyed. With (Pr2NPCl2)-Pr-i, both reactant stoichiometries produce the four-membered ring compound (Pr2NP)-Pr-i(Me3Si)P((Pr2N)-Pr-i)P(Me3Si)P (3) via different reaction schemes. Compound 3 combines with Fe-2(CO)(9) to produce a monometallic complex (4) (Pr2NP)-Pr-i(Me3Si)P((Pr2N)-Pr-i)P(Me3Si)P . Fe(CO)(4) in which the Fe(CO)(4) fragment is bonded to one of the Me3SiP centers. With the cyclic hydrazino phosphane ClP(MeNNMe)(2)PCl only the bis-phosphane substitution product, (Me3Si)(2)PP(MeNNMe)(2)PP(SiMe3)(2), is isolated. With the cyclic diazadiphosphetidine ((BuNPCl)-Bu-t)(2) a bis-phosphane substitution product [(BuNPP)-Bu-t(SiMe3)(2)](2) (10) is formed along with a cage compound [((BuNP)-Bu-t)(2)P(SiMe3)](2) (11). The new compounds have been characterized by spectroscopic techniques, and the molecular structure of 4 and 11 have been determined by X-ray crystallography.