K. Nagarajan

Solvent mediated centric/non-centric polymorph pairs of an indole derivative: Subtle variation of C–H⋯O hydrogen bonds and C–H⋯π interactions

Centric (P21/n) and non-centric (P21) polymorphic pairs of biologically active 1-(4-fluorophenyl)-6,6-dimethyl-2-phenyl-1,5,6,7-tetrahydro-4H-indol-4-one crystallized from different solvents have been elucidated via single crystal and powder X-ray diffraction studies, morphological observations and calorimetric measurements. C–H⋯O hydrogen bonding and weak intermolecular C–H⋯π interactions generate distinct packing features in the two forms.

4-(2-Methylprop-2-enyl)-1-[3-(trifluoromethyl)phenyl]thiosemicarbazide

The title compound,

trans-1,2-Difluoro-3,4,5,6,7,8-hexaphenyltricyclo[4.2.0.0 2,5 ]octa-3,7-diene

C_1_2H_1_4F_3N_3S,

1-[1-(4-Fluorophenyl)-2-methyl-5-phenyl-1H-pyrrol-3-yl]ethanone

is a biologically active antiimplantation agent. Its crystal structure is stabilized by intermolecular

1-(4-Chlorophenyl)-2,6,6-trimethyl-1,5,6,7-tetrahydro-4H-indol-4-one

N-H\cdot\cdot\cdot\cdot S

1-(4-Chlorobenzyl)-6,6-dimethyl-2-phenyl-1,5,6,7-tetrahydro-4H-indol-4-one

hydrogen bonds, which form dimmers in a head-to-tail arrangement and link them into a polymeric chain.

N-(3-Fluorophenyl)-9H-xanthen-9-ylideneamine

In order to probe the possible mechanism of the rearrangement of trans-hexaphenyldifluorotricyclooctadiene (a dimer of fluorotriphenylcyclobutadiene) to pentaphenyldihydrodifluoropentalene via C—F bond migration, a high-temperature study of the title compound,

N-[(9E)-2-Chloro-9-thia-9H-xanthen-9-ylidene]-N-(4-fluorophenyl)amine

C_{44}H_{30}F_2

Polymorphism in 1-(4-fluorophenyl)-3,6,6-trimethyl-2-phenyl-1,5,6,7-tetrahydro-4H-indol-4-one: A subtle interplay of weak intermolecular interactions

, was performed at 400 (2) K. In the title compound, there are three fused fourmembered rings with the resulting eight-membered tricyclooctadiene ring adopting a sofa conformation. The dihedral angles between the central four-membered ring and the two outer rings are 66.03 (2) and 65.39

Analysis of weak interactions involving organic fluorine: Insights from packing features in substituted 4-keto-tetrahydroindoles

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