Reaction of PhaP(C≡CBut)=NSiMe3 (1) with KP(H)Ph afforded 3-(iminophosphorano)-l-phosphaallyl potassium, [K{P(Ph)C(But)=C(H)P(Ph)a=NSiMe3}(OEta)3] [3·(OEta)3], which was recrystallized from EtaO to give a solvent-free complex, [K{P(Ph)C(But)=C(H)P(Ph)a=N-SiMe3}]∞ (3). Treatment of MeaP(C≡CPh)=NSiMe3 (2) with LiP(R)Ph (R＝H, SiMeaBut) formed 2-(iminop hosp horano)-1-phosp haallyllithium, [Li{P(Ph)C{=C(R)Ph}P(Me)a=NSiMe3}-(THE)n] (R＝H, n＝1.5, 4; R＝SiMeaBut, n＝2, 5), via a hydrogen or SiMeaBut group 1,3-P→C migration. Reaction of 4 or 5 with SnCla in 2:1 ratio in EtaO yielded P, N-chelatingtin(II) complexes [Sn{P(Ph)C{=C(R)Ph}P(Me)a=NSiMe3}a] (R＝H, 6; R＝SiMeaBut, 7). Complex 6 was also obtained by treatment of C1SnN(SiMe3)2 with 1 equiv of 4. X-ray data are provided for 3, 5, and 6. Complex 3 is polymeric in the solid state without coordinated solvent molecules, whereas both crystalline 5 and 6 are monomeric.

The lithium complex [HC(PPh2＝NSiMe3)2Li(THF)] (2) prepared by the reaction of BunLi with bis (iminophosphorano) methane reacts with GeCl2·dioxane in different stoichiometric ratios to afford [HC(PPh2＝NSiMe3)2GeCl] (3) and [(Me3SiN＝PPh2)2C＝Ge→Ge＝C(PPh2＝NSiMe3)2] (4), respectively. Bisgermavinylidene 4 can also be obtained by the reaction of 3 with [Ge{N(SiMe3)2}2] or 2. Further reaction of 4 with Me3NO afforded [(μ-N＝Ph2P)(Me3-SiN＝Ph2P)C＝Ge(OSiMe3)]2 (5), and direct reaction of elemental chalcogens (sulfur, selenium, and tellurium) with 4 afforded [(Me3SiN＝PPh2)2C＝Ge(μ-E)]2 [E＝S (6), Se (7), and Te (8)]. X-ray structures of compounds 2-8 have been determined.