6-Ferrocenoyl-7-phenylspiro[hexahydropyrrolo[1,2-c][1,3]thiazole-5,11′-indeno[1,2-b]quinoxaline]

In the title compound, [Fe(C5H5)(C32H24N3OS)], both the thiazolidine ring and the pyrrolidine ring adopt an envelope conformation, with the S atom and the phenyl-bearing C atom, respectively, as the flaps. The thiazolidine ring mean plane makes a dihedral angle of 59.08 (11)° with the pyrrolidine ring mean plane, which in turn makes a dihedral angle of 83.40 (10)° with the cyclopentane ring, indicating that the latter two rings are almost orthogonal to one another. In the crystal, a pair of C—H⋯O hydrogen bonds link the molecules forming inversion dimers. The dimers are linked via π–π interactions [centroid–centroid distance = 3.7764 (10) Å] involving the quinoxaline moieties forming chains propagating along [1-10].

In the title compound, [Fe(C 5 H 5 )(C 32 H 24 N 3 OS)], both the thiazolidine ring and the pyrrolidine ring adopt an envelope conformation, with the S atom and the phenyl-bearing C atom, respectively, as the flaps. The thiazolidine ring mean plane makes a dihedral angle of 59.08 (11) with the pyrrolidine ring mean plane, which in turn makes a dihedral angle of 83.40 (10) with the cyclopentane ring, indicating that the latter two rings are almost orthogonal to one another. In the crystal, a pair of C-HÁ Á ÁO hydrogen bonds link the molecules forming inversion dimers. The dimers are linked viainteractions [centroid-centroid distance = 3.7764 (10) Å ] involving the quinoxaline moieties forming chains propagating along [110].

Comment
Ferrocene attached compounds are well known to have biological activities, such as antimalarial and antifungal (Biot et al., 2004), antitumor (Jaouen et al., 2004), and antibacterial (Fouda et al., 2007). Against this background, and in order to obtain information on the molecular conformation of such compounds, we synthesised the title compound and report herein on its crystal structure.
In the crystal, a pair of C-H···O hydrogen bonds link the molecules forming inversion dimers (Table 1 and

Experimental
Ninhydrin (1 mmol) and 1, 2-phenylenediamine (1 mmol) were mixed and stirred with 10 ml of methanol for 10 min. To this mixture 1 mmol of thioproline and 1 mmol of Ferrocene derived dipolarophile were added and the mixture was refluxed up to the end of the reaction as observed by TLC. The solvent was removed under reduced pressure and the crude product obtained was purified by column chromatography, using a 4:1 ratio of petroleum ether and ethyl acetate.
Block-like colourless crystals suitable for the X-ray diffraction were obtained by slow evaporation of the solvent at room temperature.

Refinement
Hydrogen atoms were placed in calculated positions with C-H ranging from 0.93Å to 0.98Å and refined using the riding model approximation with U iso (H) = 1.2U eq (C).

Figure 1
The molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.

Figure 2
The crystal packing of the title compound viewed along the a axis. The C-H···O hydrogen bonds are shown as dashed lines (see Table 1 for details; H-atoms not involved in hydrogen bonding have been omitted for clarity).   where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.30 e Å −3 Δρ min = −0.33 e Å −3 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 > 2sigma(F 2 ) is used only for calculating R-factors(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.  (14) 0.04346 (9) Atomic displacement parameters (Å 2 )