(E)-1-Ferrocenyl-3-phenylprop-2-en-1-one

The title compound, [Fe(C5H5)(C14H11O)], exists as the E isomer, and the substituent is fully conjugated with the attached five-membered ring. In the ferrocene unit, the substituted cyclopentadienyl ring (Cps) plane and unsubstituted cyclopentadienyl ring (Cp) plane are almost parallel, and the C atoms in Cp and Cps are in an eclipsed conformation. In the crystal structure, molecules are linked into C(5) chains via intermolecular C—H⋯O hydrogen bonds, and neighbouring chains are assembled into sheets by intermolecular C—H⋯π(arene) hydrogen bonds along the c axis.

is the angle that the C1/H1 group makes with the normal to the Cp plane, and Cg3 is the centroid of the Cp ring.

Comment
Chalcone and its derivatives, as a natural products, have shown stronge antibacterial, antifungal, antitumor and anti-inflammatory properties, especially antileishmanial, and antimalarial (Zhai et al., 1999;Liu et al., 2001Liu et al., , 2003. Some chalcones demonstrated the ability to block voltage-dependent potassium channels (Yarishkin et al., 2008). It was proved that the replacement of the aromatic group by the ferrocenyl moiety in penicillins and cephalosporins could improve their antibiotic activity (Edwards et al., 1975). As ongoing research (Liu et al., 2008;Shi et al., 2004;Liang et al., 1998), we report herein the structure of the title compound.
The molecule of the title compound exists as the most stable configuration of (E)-isomer ( Fig.1), and all carbon atoms are sp 2 -hybridized. Although the carbon atoms and a oxygen atom form a large conjugated system, the Cps (the substituted cyclopentadienyl ring) plane and 1-plane (defined by the atoms of C11, C12, O1 and C13) and 2-plane (the phenyl ring plane) are not coplanar (Table 1). In the ferrocene moiety, the Cps plane and Cp (the unsubstituted cyclopentadienyl ring) plane are almost parallel, and the carbon atoms of Cp and Cps are in the eclipsed conformation. The Fe atom is slightly nearer to the Cps plane because the Fe-Cgs and Fe-Cg distances are 1.651 (1) and 1.658 (1) Å, respectively, where Cgs and Cg are the centroids of Cps and Cp, respectively. The Cgs-Fe-Cg angle is 178.0 (2)°.
In its packing structure, the molecules are linked into C(5) (Bernstein et al., 1995) chains via C-H···O inter-molecular hydrogen-bonds. Further more the chains and their neighboring inverse parallel chains are made up into sheets by C-H···π (arene) inter-molecular hydrogen-bonds along the c axis ( Fig. 2, Table 2).

Experimental
The title compound was synthesized according to the literature procedure (Huang et al. 1998). Crystals suitable for X-ray diffraction were obtained by slow evaporation of a solution of the solid in dichloromethane/ether (5:1 v/v) at room temperature over a period of 4 d.

Refinement
After their location in a difference map, all H atoms were fixed geometrically at ideal positions and allowed to ride on the parent C atoms, with C-H distances of 0.93 -0.98, and with U iso (H) values of 1.2U eq (C).

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating Rfactors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.