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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
3-[1-(2-Hy-droxy-anilino)ethyl-idene]-3H-chromen-2,4-dione
Ameni Brahmia1, Taicir Ben Ayed, Rached Ben Hassen
1Unité de Chimie des Matériaux et de l'Environnement, ISSBAT, Université de Tunis-ElManar, 9 Avenue Dr Zoheir SAFI, 1006 Tunis, Tunisia.
Abstract:
The title compound is a new amino-coumarin derivative, C17H13NO4, and was synthesized by the condensation of 2-amino-phenol and 3-acetyl-4-hy-droxy-coumarin. An intra-molecular N-H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, the molecules are linked into chains extending in the [010] direction by O-H⋯O hydrogen bonds. There is also a π-π stacking inter-action between the bicyclic coumarin fragment and the phenol ring [centroid-centroid distance = 3.7510 (14) Å], and these ring systems form between them a dihedral angle of 53.3 (2)°. Intermolecular hydrogen bond C-H⋯O hydrogen bonding is also observed in the interconnection of the crystal packing.
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