1′-Methyl-4′-(1-naphthyl)-1′′,2′′,3′′,4′′-tetrahydroindane-2-spiro-2′-pyrrolidine-3′-spiro-2′′-naphthalene-1,3,1′′-trione

In the title compound, C32H25NO3, the pyrrolidine ring adopts an envelope conformation, whereas the cyclohexanone ring in the tetrahydronaphthalene fused-ring system adopts a half-chair conformation. The indanedione unit is oriented at an angle of 58.9 (1)° with respect to the naphthyl ring system. Three intramolecular C—H⋯O close contacts and an intramolecular C—H⋯π interaction are observed. In the crystal, molecules associate via C—H⋯O hydrogen bonds, forming a helical chain with a C(10) motif along the b axis.

In the title compound, C 32 H 25 NO 3 , the pyrrolidine ring adopts an envelope conformation, whereas the cyclohexanone ring in the tetrahydronaphthalene fused-ring system adopts a halfchair conformation. The indanedione unit is oriented at an angle of 58.9 (1) with respect to the naphthyl ring system. Three intramolecular C-HÁ Á ÁO close contacts and an intramolecular C-HÁ Á Á interaction are observed. In the crystal, molecules associate via C-HÁ Á ÁO hydrogen bonds, forming a helical chain with a C(10) motif along the b axis. Experimental Crystal data  Table 1 Hydrogen-bond geometry (Å , ).

Related literature
Cg1 is centroid of the C1/C5/C6/C11/C12 ring. SS acknowledges the Department of Science and Technology (DST), India, for providing computing facilities under the DST-Fast Track Scheme and also thanks the Vice Chancellor and management of Kalasalingam University, Krishnankoil, for their support and encouragement.
The molecular structure of (I) is illustrated in Fig. 1. The C-C bond lengths in the pyrrolidine ring are somewhat longer in particular at two spiro junctions C1 and C2 and the C-N bond lengths are somewhat shorter than normal values. This may be due to steric forces of the bulky substituents at atoms C1 and C2 of the pyrrolidine ring (Abdul Ajees et al., 2002;Selvanayagam et al., 2005).
The indanedione moiety is planar with a maximum deviation of 0.051 (3) Å for atom C9. The keto O atoms O1 and O2 deviate from this system by 0.115 (2) and 0.177 (2) Å, respectively. The naphthyl group is also planar with a maximum deviation of 0.013 (2) Å for atom C30. This group is oriented at an angle of 58.9° with respect to the indanedione moiety.
The molecular structure is influenced by an intramolecular C-H···O hydrogen bonds and weak C-H···π interactions.
In the molecular packing, C-H···O hydrogen bonds involving atoms C17 and O1 link symmetry related molecules to form a helical shape arrangement in the unit cell ( Fig. 2 and Table 1). In addition to this another C-H···O hydrogen bonds form a C(10) chain motif in the unit cell.

Experimental
To a mixture of ninhydrin (1mmol), sarcosine (1mmol) and 2-napthalidene-1,2,3,4-tetrahydronaphthalene-1-ones (1mmol) was added and heated under reflux in methanol (20ml) until the disappearance of the starting materials as evidenced by TLC. The solvent was removed under vacuo. The crude product was subjected to column chromatography using petroleum ether-ethyl acetate as eluent. Single crystals were grown by slow evaporation from methanol. supplementary materials sup-2 Refinement H atoms were placed in idealized positions and allowed to ride on their parent atoms, with C-H distances of 0.93-0.97 Å, and Uiso(H) = 1.5U eq (C) for methyl H and Uiso(H) = 1.2U eq (C,N) for all other H atoms. Due to the lack of anomalous scatterers the absolute configuration was not determined from the X-ray diffraction data and Friedel pairs were merged. The absolute configuration of (I) is unknown.

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.