A. R. Sureshbabu

Crystal structure of 1-ferrocenyl-2-(4-methyl­benzo­yl)spiro­[11H-pyrrolidizine-3,11′-indeno[1,2-b]quinoxaline]

In the title compound the four-fused-rings system is approximately planar and the pyrrolidine rings of the pyrrolidizine fragment adopt a twist conformation. In the crystal, molecules are linked by C—H⋯O hydrogen bonds and C—H⋯π interactions, forming double-chains parallel to the c axis.

Crystal structure of 5''-(4-chloro-benzyl-idene)-4'-(4-chloro-phen-yl)-1'-methyltri-spiro[acenapthylene-1,2'-pyrrolidine-3',1''-cyclo-hexane-3'',2'''-[1,3]dioxane]-2(1H),6''-dione.

In the title compound, C36H29Cl2NO4, two spiro links connect the methyl-substituted pyrrolidine ring to the acenaphthylene and cyclohexanone rings. The cyclohexanone ring is further connected to the dioxalane ring by a third spiro junction. The five-membered ring of the acenaphthylen-1-one ring system adopts a flattened envelope conformation, with the ketonic C atom as the flap, whereas the dioxalane and pyrrolidine rings each have a twist conformation. The cyclohexenone ring assumes a boat conformation. An intramolecular C—H⋯O hydrogen-bond interaction is present. In the crystal, molecules are linked by non-classical C—H⋯O hydrogen bonds, forming chains extending parallel to the a axis.

2-(4-Bromo-benzo-yl)-1-ferrocenyl-spiro-[11H-pyrrolidizine-3,11'-indeno-[1,2-b]quinoxaline].

In the title compound, [Fe(C5H5)(C33H25BrN3O)], the fused four-ring system, 11H-indeno[1,2-b]quinoxaline is essentially planar, with a maximum deviation of 0.087 (3) Å from the least-squares plane of the attached benzene ring. The pyrrolidine rings adopt envelope conformation and make a dihedral angle of 51.76 (19)° with each other. The cyclopentadiene rings of the ferrocenyl moiety have an eclipsed conformation. The Br atom deviates by 0.0190 (9) Å from the attached benzene ring. The molecular structure features an intramolecular C—H⋯N interaction, which generates an S(8) ring motif. The crystal packing features C—H⋯O interactions, which generate R 2 2(18) centrosymmetric dimers, as well as C—H⋯π interactions.

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].

4-Ferrocenyl-1-methyl-3-benzoyl­spiro­[pyrrolidine-2,11′-indeno­[1,2-b]quinoxaline]

In the title compound, [Fe(C5H5)(C31H24N3O)], the pyrrolidine ring adopts a twist conformation. The pyrrolidine ring is almost perpendicular to the indenoquinoxaline ring system, making a dihedral angle of 84.44 (5)°. The cyclopentadienyl rings of the ferrocene moiety adopt an eclipsed conformation. The crystal packing features weak C—H⋯N and C—H⋯π interactions.

Crystal structure of 5′′-benzyl­idene-1′-methyl-4′-phenyl­tri­spiro­[ace­naphthyl­ene-1,2′-pyrrolidine-3′,1′′-cyclo­hexane-3′′,2′′′-[1,3]dioxane]-2,6′′-dione

In the title trispiro compound, both the methyl-substituted pyrrolidine and dioxalane rings adopt a twist conformation. The cyclopentanone ring of the acenapthylen-1-one system adopts flattened envelope conformation, and the cyclohexanone attached to the dioxalane ring adopts boat conformation. In the crystal, centrosymmetrically related molecules are linked into dimers forming rings of (10) graph-set motif, which are further connected into chains parallel to the b axis by C—H⋯O contacts forming rings of (8) graph-set motif.

Crystal structure of methyl 3′-benzamido-4′-(4-meth­oxy­phen­yl)-1′-methyl­spiro­[indeno­[1,2-b]quinoxaline-11,2′-pyrrolidine]-3′-carboxyl­ate

In the title compound, the mean plane through pyrrolidine ring is approximately orthogonal to the mean plane of the cyclopentane ring, making a dihedral angle of 88.78 (10)°. An intramolecular N—H⋯N interaction is observed. The crystal packing features C—H⋯O hydrogen bonds.

1′-Methyl-4′-(3,4,5-tri­methoxy­phenyl)­di­spiro­[indene-2,3′-pyrrolidine-2′,3′′-indole]-1,2′',3(1′′H)-trione

The pyrrolidine ring of the title compound, C29H26N2O6, adopts a twist conformation. The structure is stabilized by weak intramolecular C—H⋯O interactions as well as by intermolecular C—H⋯O, N—H⋯O and N—H⋯N interactions.

5,7-Di­bromo-1′-methyl-2′-(4-methoxy­benzoyl)-1H-indole-3-spiro-2′-pyrrolidine-3′-spiro-3′′-1H-indole-2,2′′(3H,3′′H)-dione methanol solvate

The pyrrolidine ring of the title compound, C27H21Br2N3O4·CH4O, adopts an envelope conformation. The methanol solvent molecule is involved in intermolecular hydrogen bonds. The molecular structure is stabilized by C—H⋯O interactions, and the packing is stabilized by N—H⋯O, O—H⋯O and O—H⋯N intermolecular interactions.

5,7-Di­bromo-4′-(4-bromo­benzoyl)-1′-methyl-1H-indole-3-spiro-2′-pyrrolidine-3′-spiro-3′′-1H-indole-2,2′′(3H,3′′H)-dione methanol solvate

The pyrrolidine ring of the title compound, C26H18Br3N3O3·CH4O, adopts an envelope conformation. The molecular structure is stabilized by C—H⋯O interactions and the packing is stabilized by N—H⋯O and O—H⋯N intermolecular interactions, which also include the methanol solvent molecules.