Crystal structures of 3‐methyl‐2(1H)‐quinoxalinone and three substituted derivatives

Denise Mondieig (1) , Philippe Négrier (1) , Stéphane Massip (2) , Jean-Michel Leger (2) , Chakir Jarmoumi (3) , Brahim Lakhrissi (3)

1 LOMA - Laboratoire Ondes et Matière d'Aquitaine
2 Laboratoire de Pharmacochimie
3 Laboratoire de Chimie d'Agroressources et Génie des Procédés

3-Methyl-2(1H)-quinoxalinone and three derivatives (3,7-dimethyl-2(1H)-quinoxalinone, 3-methyl-6,7-dichloro-2(1H)-quinoxalinone and 3-methyl-7-nitro-2(1H)-quinoxalinone) have been synthesised and analysed by 1H NMR and IR spectral spectroscopies. The crystal structures have been determined at room temperature from X-ray single crystal diffraction data for three of them and from powder diffraction data for the nitro derivative. 3-Methyl-2(1H)-quinoxalinone crystallises in the P21/c monoclinic system, 3,7-dimethyl-2(1H)-quinoxalinone in the Pbca orthorhombic system and the two others compounds in the Pequation image triclinic system. For the nitro derivative, C-H..N short contacts are established between the carbon of the methyl and the double bounded nitrogen of the ring. For the three other compounds N-H..O hydrogen bonds involve the atoms of the heterocyclic ring.

Mots clés: 3-methyl-2(1H)-quinoxalinone derivative; intermolecular interaction; powder structure; single crystal structure; synthesis

Domaines: Cristallographie

Denise Mondieig, Philippe Négrier, Stéphane Massip, Jean-Michel Leger, Chakir Jarmoumi, et al.. Crystal structures of 3‐methyl‐2(1H)‐quinoxalinone and three substituted derivatives. Journal of Physical Organic Chemistry, 2011, 24 (12), pp.1193-1200. ⟨10.1002/poc.1846⟩. ⟨hal-00668396⟩