title: Crystal structures of three 1-oxo-1,2-di-hydro-naphthalene derivatives: dimethyl 4-(4-meth-oxy-phen-yl)-2-(4-methyl-phen-yl)-1-oxo-1,2-di-hydro-naphthalene-2,3-di-carboxyl-ate, dimethyl 1-oxo-2-(pyren-4-yl)-4-(thio-phen-2-yl)-1,2-di-hydro-naphthalene-2,3-di-carboxyl-ate and ethyl 1-oxo-2-phenyl-2,4-bis-(thio-phen-2-yl)-1,2-di-hydro-naphthalene-3-carboxyl-ate.
abstract: In the title 1-oxo-1,2-di-hydro-naphthalene derivatives, C28H24O6, (I), C34H22O5S, (II), and C27H20O3S2, (III), the cyclo-hexa-1,3-diene rings of the 1,2-di-hydro-naphthalene ring systems adopt half-chair, boat and half-chair conformations, respectively. The carbonyl O atoms attached to the di-hydro-naphthalene ring systems are each significantly deviated from the mean plane of the 1,2-di-hydro-naphthalene ring system, by 0.6162 (12) Å in (I), 0.6016 (16) Å in (II) and 0.515 (3) Å in (III). The mean planes of the 1,2-di-hydro-naphthalene ring systems make dihedral angles of 85.83 (3), 88.19 (3) and 81.67 (8)°, respectively, with the methyl-phenyl ring in (I), the pyrene ring in (II) and the phenyl ring in (III). In (I), the mol-ecular structure is stabilized by an intra-molecular C-H⋯O hydrogen bond, generating anS(6) ring motif. In the crystal of (I), mol-ecules are linked by an inter-molecular C-H⋯O hydrogen bond, which generates aC(8) zigzag chain running along [100]. Adjacent chains are further connected by C-H⋯π and offset π-π inter-actions [centroid-centroid distance = 3.6572 (9) Å], forming a double-chain structure. In the crystals of (II) and (III), mol-ecules are linked into chain structures by offset π-π inter-actions with centroid-centroid distances of 3.5349 (12) and 3.8845 (13) Å for (II) and 3.588 (2) Å for (III). In (II) and (III), the thio-phene rings are orientationally disordered over two sites, with occupancy ratios of 0.69:0.31 for (II), and 0.528 (4):0.472 (4) and 0.632 (5):0.368 (5) for (III).
authors.affiliation: Department of Physics, RKM Vivekananda College (Autonomous), Chennai 600 004, India.
authors.forename: S
authors.initials: S
authors.lastname: Gopinath
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: Jeyachandran
authors.initials: J
authors.lastname: Karunakaran
authors.affiliation: Department of Organic Chemistry, University of Madras, Guindy Campus, Chennai 600 025, India.
authors.forename: Meganathan
authors.initials: M
authors.lastname: Nandakumar
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: 1-oxo-1,2-di­hydro­naphthalene; crystal structure; hydrogen bonding; pyrene; thio­phene