title: Crystal structures of three carbazole derivatives: 12-ethyl-7-phenyl-sulfonyl-7H-benzofuro[2,3-b]carbazole, (1), 2-(4,5-dimeth-oxy-2-nitro-phen-yl)-4-hy-droxy-9-phenyl-sulfonyl-9H-carbazole-3-carbaldehyde, (2), and 12-phenyl-7-phenyl-sulfonyl-7H-benzofuro[2,3-b]carbazole, (3).
abstract: The three title compounds, C26H19NO3S, (1), C27H20N2O8S, (2), and C30H19NO3S, (3), are carbazole derivatives, where (1) and (3) are heterocycle-containing carbazoles with a benzo-furan moiety fused to a carbazole unit. In (2), a di-meth-oxy-nitro-phenyl ring is attached to the carbazole moiety. In the three derivatives, a phenyl-sulfonyl group is attached to the N atom of the carbazole unit. Compound (1) crystallizes with two independent mol-ecules in the asymmetric unit (AandB). The carbazole skeleton in the three compounds is essentially planar. In compound (1), the benzene ring of the phenyl-sulfonyl moiety is almost orthogonal to the carbazole moiety, with dihedral angles of 85.42 (9) and 84.52 (9)° in mol-eculesAandB, respectively. The benzene ring of the phenyl-sulfonyl group in compounds (2) and (3) are inclined to the carbazole moiety, making dihedral angles of 70.73 (13) and 81.73 (12)°, respectively. The S atom has a distorted tetra-hedral configuration in all three compounds. In the crystals, C-H⋯O hydrogen bonds give rise toR22(12) inversion dimers for compound (1), and toR22(24) inversion dimers andR44(40) ring motifs for compound (2). The crystal packing in (1) also features C-H⋯π and π-π inter-actions [shortest inter-centroid distance = 3.684 (1) Å], leading to supra-molecular three-dimensional aggregation. In the crystal of compound (2), the combination of the various C-H⋯O hydrogen bonds leads to the formation of a three-dimensional network. In the crystal of compound (3), mol-ecules are linked by C-H⋯O hydrogen bonds, forming chains running parallel to theaaxis, and the chains are linked by C-H⋯π inter-actions, forming corrugated sheets parallel to theabplane.
authors.affiliation: Department of Physics, Ethiraj College for Women (Autonomous), Chennai 600 008, India.
authors.forename: Rajeswari
authors.initials: R
authors.lastname: Gangadharan
authors.affiliation: Department of Physics, RKM Vivekananda College (Autonomous), Chennai 600 004, India.
authors.forename: P
authors.initials: P
authors.lastname: Narayanan
authors.affiliation: Department of Physics, RKM Vivekananda College (Autonomous), Chennai 600 004, India.
authors.forename: K
authors.initials: K
authors.lastname: Sethusankar
authors.affiliation: Department of Organic Chemistry, University of Madras, Guindy Campus, Chennai 600 025, India.
authors.forename: Velu
authors.initials: V
authors.lastname: Saravanan
authors.affiliation: Department of Organic Chemistry, University of Madras, Guindy Campus, Chennai 600 025, India.
authors.forename: Arasambattu K
authors.initials: AK
authors.lastname: Mohanakrishnan
keywords: C—H⋯O hydrogen bonds; C—H⋯π inter­actions; aggregation; benzo­furan; carbazole derivatives; crystal structure; inversion dimers