Cyclische diazastannylene: XXII. Zur umsetzung eines bis(amino)stannylens mit organylphosphanen, -methylen-phosphoranen, -phosphaniminen, -oxiden und -sulfiden

1,3-Di-t-butyl-2,2-dimethyl-1,3,2,4λ²-diazasilastannetidin (I) was allowed to react with the phosphanes PEt₃ and PPh₃ as well as with Me₃PCH₂, Ph₃PCH₂, Ph₃PNH, Me₃PO and Et₃PS. While the phosphor ylides and the phosphane oxide interact with I to yield crystalline acid-base adducts, no stable adducts can be isolated with the phosphanes and the phosphane sulfide. The adduct of Ph₃PCH₂ and I crystallizes with one benzene molecule per formula unit in the monoclinic space group P2₁/c (a 1188.2(8), b 1438.4(2), c 2169.4(5) pm, β 106.5(4)°). I and Ph₃PCH₂ are linked together by a SnC bond of 240.3(10) pm. The electron transfer from the ylide-carbon to the tin atom can be evaluated from the PC bond length of 174.3(11) pm. The phosphaneimine reacts with I by displacement of the tin atom in I by hydrogen atoms yielding N, N ′-di-t-butyl-Si, Si-dimethylsilazanean and Sn(NPPh₃)₄, and oxidation at the tin atom. 3 molecules of benzene are crystallizing together with one formula unit of Sn(NPPh₃)₄ (monoclinic; C2/c; a 2470.0(4), b 1643.6(6), c 2382.7(4) pm, β 128.1(3)°). The tin atom is the centre of a tetrahedron of nitrogen atoms, the mean SnN-bond length (197.5 pm) being the shortest so far reported.