Abstract: | Bifunctionalized 1 H‐Phosphirene and g1‐1‐Phosphaallene Tungsten Complexes The tungsten(0) complex {(Me3Si)2HCPC(Ph)=N}W(CO)5] 1 reacts upon heating with acetylene derivatives 2 a–d in toluene to form benzonitrile and the complexes {(Me3Si)2HCPC(R)=COEt} · W(CO)5] 5 a–d ( 5 a : R = SiMe3; 5 b : R = SiPh3; 5 c : R = SnMe3; 5 d : R = SnPh3) and {(Me3Si)2HCP=C=C(OEt)R} · W(CO)5] 6 a, b ( 6 a : R = SnMe3; 6 b : R = SnPh3), which have been isolated by chromatography; complexes 5 c and 6 a have been characterized as mixtures. Spectroscopic and mass spectrometric data are discussed. The crystal structure of the compound 5 a was determined by X‐ray single crystal structure analysis ( 5 a : space group P21/n, Z = 4, a = 977.6(2) pm, b = 1814.6(4) pm, c = 1628.0(4) pm, β = 93.95(2)°). |