title: (-)-(S)-N,N'-Bis[1-(1-naphth-yl)eth-yl]-oxalamide.
abstract: The title mol-ecule, C(26)H(24)N(2)O(2), displays C(2) symmetry, with the mol-ecule located on a twofold axis perpendicular to the plane of the oxalamide unit -NH-CO-CO-NH-. The oxalamide core deviates from planarity, as reflected by the O=C-C=O and N-C-C-N torsion angles of 164.3 (5) and 163.2 (5)°, respectively. The naphthyl groups are oriented toward the same face of the oxalamide mean plane and make a dihedral angle of 43.76 (8)°. This conformation is suitable for the formation of inter-molecular N-H⋯O hydrogen bonds, giving noncentrosymmetric dimers incorporating R(2) (2)(10) ring motifs. These nonbonding inter-actions propagate along the 6(1) screw axis normal to the mol-ecular twofold axis, resulting in a single-stranded right-handed helix parallel to [001]. In the crystal, Δ helices are arranged side-by-side and inter-act through π-π contacts between naphthyl groups. The shortest centroid-centroid separation between inter-acting benzene rings is 3.623 (4) Å.
authors: Sylvain
authors: S
authors: Bernès
authors: Guadalupe
authors: G
authors: Hernández
authors: Jaime
authors: J
authors: Vázquez
authors: Alejandra
authors: A
authors: Tovar
authors: René
authors: R
authors: Gutiérrez
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