Synthesis and crystal structures of the homoleptic phosphoraneiminato cations [E(NPPh3)(3)](+) (E = S, Se, Te) with iodide and triiodide counter ions

N-Iod-triphenylphosphaneimine, INPPh3, reacts with the chalcogenes sulfur, selenium and tellurium in boiling tetrahydrofuran to give the phosphoraneim inato complexes [E(NPPh3)(3)](+)[1/2I(3)(-), 1/2I(-)] . TKF (E = S (1), E = Se (2)) and [Te(NPPh3)(3)]I-+(3)- (3), respectively. The componds form red crystals which are characterized by IR spectroscopy and by crystal structu re determinations. The homoleptic cations [E(NPPh3)(3)](+) have pyramidal s tructures with short EN and PN bond lengths, corresponding to double bonds. 1: Space group Pa (3) over bar, Z = 8, lattice dimensions at -80 degrees C : a = b = c = 2192.9(1) pm, R-1 = 0.0299. 2: Space group Pa 3, Z = 8, latti ce dimensions at -80 degrees C: a = b = c = 2202.5(1) pm, R-1 = 0.0357. 3. Space group Pca2(1), Z = 4, lattice dimensions at -90 degrees C; a = 1075.8 (2); b = 1988.8(4); c = 2437.2(3) pm, R-1 = 0.0443.