Anyles of 4-benzoylpyridine – Crystal structure and spectroscopic properties

Two novel anyles of 4-benzolylpyridine, namely N,N-diethyl-N′-[(Z)-phenyl(pyridin-4-yl)methylidene]benzene-1,4-diamine and its N-ethylpyridinium salt were synthesized and elucidated in detail spectroscopically, thermally and structurally, using linear polarized solid-state IR-spectroscopy, UV-spectroscopy, TGA, DSC, DTA and positive and negative ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and electronic spectra of the compounds. The crystal structure of an anyle-pyridine derivative, N,N-diethyl-N′-[(Z)-phenyl(pyridin-4-yl)methylidene]benzene-1,4-diamine, is reported for the first time; the material crystallized in the triclinic P-1 space group and only one short contact of length 3.16 Å was observed between two neighbouring pyridine fragments. A bathochromic shift in λmax of 170 nm resulted from N-anylation and a 95 nm solvatochromic shift of N,N-diethyl-N′-[(Z)-phenyl(pyridin-4-yl)methylidene]benzene-1,4-diamine were obtained depending on solvent type.