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Updated: Aug 7, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
(Z)-2,3-Di-chloro-1,4-bis-(4-chloro-phen-yl)but-2-ene-1,4-dione
Ram K Tittal1, Satish Kumar2, R N Ram1
1Department of Chemistry, Indian Institute of Technology Delhi, Hauzkhas, New Delhi 110 016, India.
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.
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