Ethyl 3-oxo-2-(2-phenyl­hydrazinyl­idene)butano­ate: a re-determination

The previous crystallographic studies [Wang et al. (2005 ▶). Huaxue Yanjiu 16, 29–32; Wang et al. (2007 ▶). Youji Huaxue, 27, 524] of the title compound, C(12)H(14)N(2)O(3), gave only the unit-cell dimensions and an R factor with no other details available: the full structure is presented here. The eth­oxy group is disordered over two orientations with refined occupancies of 0.642 (15):0.358 (15). The nine C atoms and two N atoms of the 1-phenyl-2-(propan-2-yl­idene)hydrazine segment of the mol­ecule are close to being coplanar, with a maximum deviation of 0.0779 (14) Å for the phenyl­amino N atom and an intra­molecular N—H⋯O hydrogen bond generates an S(6) ring. In the crystal, pairs of C—H⋯O hydrogen bonds link mol­ecules into inverson dimers, generating R (2) (2)(16) loops.