(Z)-3-(4-Bromoanilino)-1-ferrocenylbut-2-en-1-one

In the title compound, [Fe(C5H5)(C15H13BrNO)], formed from the reaction of ferrocenoylacetone and 4-bromoaniline, the molecular structure is stabilized by an intramolecular N—H⋯O hydrogen bond between the amine and carbonyl groups.

In the title compound, [Fe(C 5 H 5 )(C 15 H 13 BrNO)], formed from the reaction of ferrocenoylacetone and 4-bromoaniline, the molecular structure is stabilized by an intramolecular N-HÁ Á ÁO hydrogen bond between the amine and carbonyl groups.

Comment
Ferrocenes containing enaminones have attracted interest because they can be used as good chelating ligands for transition metals (Shi et al., 2004(Shi et al., , 2005(Shi et al., , 2008. On the other hand, anions generated from these molecules offer alternatives to conventional ligands (cyclopentadienyl anions) in the formation of transition metal complexes for olefin polymerization catalysts (Ye et al., 2008).
The title compound, [Fe(C 5 H 5 )(C 15 H 13 BrNO)], (I), is a Schiff base molecule resulting from the reaction of ferrocenoylacetone and 4-bromoaniline. It crystallizes in the monoclinic space group P2 1 /c and its asymmetric unit contains only one title molecule (Fig. 1).
The distances between the cyclopentadienyl ring centroids and the Fe atom are 1.644 Å and 1.634 Å, respectively. The cyclopentadienyl rings of the ferrocenyl group are parallel with a dihedral angle of 1.9 (3)° between the corresponding least-squares planes. These metrical parameters are typical of the η 5 ···Fe···η 5 coordination of the ferrocenyl moiety. The O1-C11-C12-C13-N1 skeleton is coplanar (rms deviation = 0.005 Å). The C≐O, C≐C and C≐N bond lengths are intermediate between their corresponding double and single bonds indicating that the π-system is partially delocalized in the framework. Likewise, the skeleton is nearly coplanar with the C 5 H 4 ring with an angle of 6.9 (2)° between the mean planes. On the other hand, the angle between the least-squares planes of O1-C11-C12-C13-N1 and the bromophenyl ring C16/C20 is 33.8 (1)° out of the plane showing the lack of conjugation between both systems.
The molecular structure of the enaminone-containing compound is also stabilized by an intramolecular N-H···O hydrogen bond between the amine and the carbonyl groups (Table 1). This feature has been previously described by Fuentealba et al. (2008).

Refinement
The NH hydrogen atom was located in a difference Fourier map and geometrically refined with U iso (H) = 1.2U eq (N). The other H atoms positions were calculated after each cycle of refinement using a riding model with C-H distances in the range 0.95-0.98 Å and U iso (H) = 1.2U eq (C). Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are presented at 30% probability level. H atoms are shown as a small spheres of arbitrary radius.