Molecular Ions of TRansient Species: Vinylamine Cation

Article abstract of DOI:10.1002/hlca.19840670128

Vinylamine 1 was prepared by thermolysis of cyclobutylamine and its photoelectron spectrum was measured.I¹_a = 8.20 eV and I¹_v = 8.65 eV were found, the dominant vinrational progression (ν<*> = 725 cm^-1) indicating that in the course of 1(X) -> 1⁺(X<*>) flattening around the N-atom occurs.The Franck-Condon profile of this band, however, suggests that a skeletal mode of ν<*> ca. 1400 cm^-1 (observed also in the iso-?-electronic systems vinyl-alcohol-cation and allyl radical) may also be excited.Comparison with the data for the isomer acetaldehyde-imine 2 and its cation 2⁺ shows that the isomer couple 1/2 constitutes a further notable example for a relative thermochemical stability inversion on going from neutrals to the cations.