Fun, H.-K.Padaki, M.Holla, S.R.Isloor, A.M.Chantrapromma, S.2026-02-052009Acta Crystallographica Section E: Structure Reports Online, 2009, 65, 6, pp. o1320-o132116005368https://doi.org/10.1107/S160053680901784Xhttps://idr.nitk.ac.in/handle/123456789/27617The mol-ecule of the title oxobutanoate derivative, C<inf>12</inf>H <inf>13</inf>C<inf>l</inf>N<inf>2</inf>O<inf>3</inf>, adopts a keto-hydrazo tautomeric form and is roughly planar, the angle between the benzene ring and the mean plane through the hydrazone and aliphatic chain being 1.49 (6)°. This planarity is further aided by the formation of an intra-molecular N - H?O hydrogen bond which generates an S(6) ring motif. The aromatic ring and aliphatic chain have a trans configuration with respect to the N - N bond. In the crystal packing, centrosymmetric R 2 2(16) dimers are formed through pairs of weak C - H?O(3-oxo) inter-actions. These dimers are linked together through weak C - H?O(carboxyl-ate C=O) inter-actions into ribbons along the b-axis direction. These ribbons are stacked along the a-axis direction. The crystal also exhibits Cl?Cl [3.4988 (6) Å] and C?O [3.167 (2)-3.335 (2) Å] short contacts.