Bis(phosphino)amines Ph2PN(R)PPh2 (R = Et, Pr-n, Bu-n) react with stoichiometric amounts of trimethylsilyl azide to give the trimethylsilyliminophosphorano(amino)phosphines Me3SiN=PPh2N(R)PPh2 (1, R = Et; 2, R = Pr-n; 3, R = Bu-n) as crystalline compounds. The structure of 2 has been determined by single-crystal X-ray analysis. (Crystal data for 2: monoclinic, P2(1)/c, a = 10.235(1) Angstrom, b = 16.802(2) Angstrom, c = 17.075(2) Angstrom, beta = 101.05(1)degrees, V = 2882.9(5) Angstrom (3), Z = 4.) The structure of 2, which is the first example of an iminophosphoranophosphine with the P-III-N-P-V=N skeleton, was solved by direct methods and refined to R = 0.044. Compound 2 readily reacts with elemental sulfur, selenium, or phosphoryl azide to give fully oxidized phosphinimines Ph2P(E)N(Pr-n)Ph2P=NSiMe3 (4, E = S: 5, E = Se: 6, E = NP(O)(OPh)(2)). Compounds 4-6 are very sensitive to moisture and readily undergo desilylation to give the parent phosphinimines Ph2P(E)N(Pr-n)Ph2P=NH, which can be isolated as moderately stable crystalline solids. The phosphiniminophosphine 2 and the oxidized phosphinimines (4 and 5) react with CpTiCl3 to give new nitrogen-bound Ti(IV) derivatives Ph2P(E)N(Pr-n)Ph2P=NTi(Cp)Cl-2 (10, E = Lone pair: 11. E = S: 12, E = Se). Compounds 1-3 readily react with rhodium(I), palladium(II), and platinum(II) complexes to give five-membered metallacycles via phosphorus(III) and imine nitrogen coordination.