title: Isotypic crystal structures of 2,6-di-bromo-N,N-bis-(4-nitro-phen-yl)aniline and 2,6-di-chloro-N,N-bis-(4-nitro-phen-yl)aniline.
abstract: In the mol-ecules of the two isotypic title compounds, C18H11Br2N3O4 (I) and C18H11Cl2N3O4 (II), the tri-phenyl-amine N atoms show no sign of pyramidalization, with marginal displacements of the N atoms from the mean plane of the three connecting C atoms: 0.0058 (13) Å for the Br compound (I) and 0.0074 (9) Å for the Cl compound (II). In the crystals, mol-ecules are linked through C-H⋯O hydrogen bonds between phenyl rings and nitro groups and by X⋯O (X = Br, Cl) inter-actions, that are shorter than the sum of the van der Waals radii, leading to a three-dimensional network.
authors.affiliation: Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163, A-1060 Vienna, Austria.
authors.forename: Paul
authors.initials: P
authors.lastname: Kautny
authors.affiliation: Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163, A-1060 Vienna, Austria.
authors.forename: Johannes
authors.initials: J
authors.lastname: Fröhlich
authors.affiliation: Institute for Chemical Technologies and Analytics, Division of Structural Chemistry, Vienna University of Technology, Getreidemarkt 9/164-SC, A-1060 Vienna, Austria.
authors.forename: Berthold
authors.initials: B
authors.lastname: Stöger
authors.affiliation: Institute for Chemical Technologies and Analytics, Division of Structural Chemistry, Vienna University of Technology, Getreidemarkt 9/164-SC, A-1060 Vienna, Austria.
authors.forename: Matthias
authors.initials: M
authors.lastname: Weil
keywords: aryl­amines; crystal structure; isotypism