Synthesis of aryliminoacetonitriles under FVT conditions or by dehydrogenation of arylaminoacetonitriles: an NMR and UV-photoelectron spectroscopy study

• Published in: Tetrahedron Vol. 65; no. 51; pp. 10581 - 10589
• Main Authors: Leśniak, Stanisław, Chrostowska, Anna, Kuc, Dawid, Maciejczyk, Małgorzata, Khayar, Saïd, Nazarski, Ryszard B., Urbaniak, Łukasz
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 19.12.2009; Elsevier
• Subjects: Aliphatic compounds; Chemical Sciences; Chemistry; Chemistry, Organic; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with only one n hetero atom and condensed derivatives; Inorganic chemistry; Organic chemistry; Physical Sciences; Preparations and properties; Science & Technology; 4 MEMBERED RINGS; EFFICIENT IMPLEMENTATION; EXCITATION-ENERGIES; IONIZATION-POTENTIALS; NITROGEN ATOM; GAS-PHASE; FLASH VACUUM THERMOLYSIS; CHEMICAL EVOLUTION; THERMAL-DECOMPOSITION; HCN DIMERS; Nitrile; Nitrogen heterocycle; Enthalpy; Lactam; Flash pyrolysis; NMR spectrometry; Thermal reaction; Allylic compound; Fragmentation; Hydrogen 1; Photoelectron spectrometry; Aromatic compound; Chemical synthesis; Carbon 13; β-Lactams; Prediction; Dimethyl butynedioate; Theoretical study; Coupling constant; Ultraviolet spectrometry; Chemical shift; Dehydrogenation; Ene reaction; Acetonitrile; Density functional method
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/j.tet.2009.10.080

The synthesis of [( E)-arylimino]-acetonitriles 3 has been described. It was found that the title compounds can be obtained on the three ways, namely by: (i) dehydrogenation of arylaminoacetonitriles 1, (ii) thermal fragmentation of 1-aryl-4-cyano-β-lactams 4 and (iii) retro-ene reaction of (allyl- p-methoxyphenyl-amino)-acetonitrile ( 7a) under FVT conditions. 1H and 13C NMR spectra of compounds 3, 5 and 6, and all their precursors 1 and 4, were recorded and analysed in detail using chemical shifts δ H and δ C [from GIAO DFT B3LYP/6-31(d) calculations] and J-couplings predicted at the DFT B3LYP/IGLO-II level. Also, UV-photoelectron spectra of 4a, d and 3a, d were measured and analysed considering the theoretical evaluation of their ionisation potentials. [Display omitted]