title: (Z)-2,3-Di-chloro-1,4-bis-(4-chloro-phen-yl)but-2-ene-1,4-dione.
abstract: The title compound, C16H8Cl4O2, crystallizes with two independent mol-ecules in the asymmetric unit. Both mol-ecules have a Z conformation around the central double bond and they show significantly different C-C-C-O torsion angles between the aromatic ring and the carbonyl group [30.1 (7) and 3.9 (7)° in one molecule and 23.5 (7) and 9.3 (8)° in the other]. The crystal packing shows short halogen Cl⋯O [3.003 (5) and 3.246 (4) Å] and Cl⋯Cl [3.452 (2) Å] contacts and aromatic C-H⋯Cl and C-H⋯O inter-actions link the molecules, resulting in chains propogating along [100]. The crystal structure also features π-π stacking inter-actions between aromatic units of the two independent mol-ecules, with a centroid-centroid distance of 3.9264 (6) Å.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Delhi, Hauzkhas, New Delhi 110 016, India.
authors.forename: Ram K
authors.initials: RK
authors.lastname: Tittal
authors.affiliation: Department of Chemistry, St. Stephen's College, University Enclave, Delhi 110 007, India.
authors.forename: Satish
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Department of Chemistry, Indian Institute of Technology Delhi, Hauzkhas, New Delhi 110 016, India.
authors.forename: R N
authors.initials: RN
authors.lastname: Ram
keywords: crystal structure