1, 3, 4, 4'-Tetra(triphenylphosphanimin)-2-iodo-2-butenal-4-carboniumiodid, [O=C(NPPh₃)C(I)=C(NPPh₃)-C(NPPh₃)₂]⁺I^-

Pale yellow single crystals of [O=C(NPPh₃)C(I)=C(NPPh₃)-C(NPPh₃)₂]⁺I^-·1.5 thf (1·1.5 thf) have been obtained by the reaction of INPPh₃ with thallium in thf suspension. They are characterized by IR spectroscopy and by a crystal structure determination. 1·1.5 thf crystallizes in the monoclinic space group P2₁/n, Z = 4, lattice dimensions at -83?C: a = 1101.7(1), b = 3449.0(2), c = 2000.4(1) pm, β = 104.88(1)?, R₁ = 0.0382. 1 can be understood as a cationic variation of (Z)-2-butenale in which all H atoms are substituted by triphenylphosphoraneimine residues and by a iodine atom, respectively.