title: 1H and 13C NMR identification of unexpected 3,4-dihydroquinoxalines in the syntheses of 1,5-benzodiazepine derivatives.
abstract: The reaction between o-phenylenediamines, dehydroacetic acid and aromatic aldehydes is shown to give not only the expected 1,5-benzodiazepine derivative but also a 3,4-dihydroquinoxaline, the structure of which was determined by its 1H and 13C 1D and 2D NMR spectra.
authors.affiliation: Département de Chimie, Faculté des Sciences, Université Mohammed V, Rabat, Morocco.
authors.forename: E M
authors.initials: EM
authors.lastname: Tjiou
authors.forename: E G
authors.initials: EG
authors.lastname: Lhoussaine
authors.forename: D
authors.initials: D
authors.lastname: Virieux
authors.forename: A
authors.initials: A
authors.lastname: Fruchier
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D001569:Benzodiazepines / Q000032:analysis / Q000138:chemical synthesis*; D002247:Carbon Isotopes; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008968:Molecular Conformation; D010655:Phenylenediamines / Q000737:chemistry*; D011522:Protons; D011753:Pyrones / Q000737:chemistry*; D011810:Quinoxalines / Q000032:analysis* / Q000737:chemistry*
chemical_list: D000447:Aldehydes; D002247:Carbon Isotopes; D010655:Phenylenediamines; D011522:Protons; D011753:Pyrones; D011810:Quinoxalines; D001569:Benzodiazepines; C027493:dehydroacetic acid