Suhana Arshad

A new chalcone structure of (E)-1-(4-Bromophenyl)-3-(napthalen-2-yl)prop-2-en-1-one: Synthesis, structural characterizations, quantum chemical investigations and biological evaluations.

The structure of (E)-1-(4-Bromophenyl)-3-(napthalen-2-yl)prop-2-en-1-one (C19H13BrO) crystallized in the triclinic system of P-1 space group. The unit cell dimensions are: a=5.8944 (9)Å, b=7.8190 (12)Å, c=16.320 (2)Å, α=102.4364 (19)°, β=95.943 (2)°, γ=96.274 (2)° and Z=2. The physical properties of this compound was determined by the spectroscopic methods (FTIR and (1)H and (13)C NMR). Quantum chemical investigations have been employed to investigate the structural and spectral properties. The molecular structure, vibrational assignments, (1)H and (13)C NMR chemical shift values, non-linear optical (NLO) effect, HOMO-LUMO analysis and natural bonding orbital (NBO) analysis were calculated using HF and DFT/B3LYP methods with 6-311++G(d,p) basis set in the ground state. The results show that the theoretical calculation of the geometrical parameters, vibrational frequencies and chemical shifts are comparable with the experimental data. The crystal structure is influenced and stabilized by weak C-H⋯π interactions connecting the molecules into infinite supramolecular one dimensional ladder-like arrangement. Additionally, this compound is evaluated for their antibacterial activities against gram positive and gram negative strains using a micro dilution procedure and shows activities against a panel of microorganisms.

2-Oxo-2-phenyl­ethyl benzoate

In the title compound, C15H12O3, the terminal phenyl rings make a dihedral angle of 86.09 (9)° with each other. In the crystal, a pair of intermolecular C—H⋯O hydrogen bonds link the molecules, forming a dimer with an R 2 2(10) ring motif.

(E)-1-(Anthracen-9-yl)-3-(2-chloro-6-fluoro­phen­yl)prop-2-en-1-one: crystal structure and Hirshfeld surface analysis

In the title compund, the enone moiety adopts an E conformation. An intramolecular C—H⋯F hydrogen bond generates an S(6) ring motif. In the crystal, molecules are arranged into centrosymmetric dimers via pairs of C—H⋯F hydrogen bonds. The crystal structure also features C—H⋯π and π–π interactions. Hirshfeld surface analysis was used to confirm the existence of intermolecular interactions.

5-(4,4′′-Difluoro-5′-hy­droxy-1,1′:3′,1′′-terphenyl-4′-yl)-3-(morpholin-4-ylmeth­yl)-1,3,4-oxadiazole-2(3H)-thione

In the title compound, C25H21F2N3O3S, the morpholine ring adopts a chair conformation. The 1,3,4-oxadiazole-2(3H)-thione group makes dihedral angles of 78.69 (8), 53.56 (7) and 55.30 (9)° with the benzene rings. In the crystal, O—H⋯O, C—H⋯S and C—H⋯F hydrogen bonds linked the molecules into layers lying parallel to the ab plane. Weak C—H⋯π interactions also occur.

2-(4-Chlorophenyl)-2-oxoethyl 3-(trifluoromethyl)benzoate

In the title compound, C16H10ClF3O3, the two benzene rings are slightly twisted from each other, with a dihedral angle of 15.50 (8)° between the planes. In the crystal, intermolecular C—H⋯O hydrogen bonds link the molecules into a layer parallel to the bc plane.

(E)-1,3-Bis(anthracen-9-yl)prop-2-en-1-one: crystal structure and DFT study

In the crystal, molecules are connected into chains along [100] via weak C—H⋯π interactions. The observed band gap of 3.03 eV is in excellent agreement with that (3.07 eV) calculated using density functional theory (DFT) at the B3LYP/6–311++G(d,p) level. The Hirshfeld surface analysis indicates a high percentage of C⋯H/H⋯C (41.2%) contacts in the crystal.

4-tert-Butyl-N-[(2,6-dimethyl-phen-yl)carbamothio-yl]benzamide.

The asymmetric unit of the title compound, C20H24N2OS, consists of two crystallographically independent molecules. In each molecule, an intramolecular N—H⋯O hydrogen bond forms an S(6) ring motif. The dihedral angles between the terminal benzene rings in the two molecules are 75.52 (7) and 42.80 (7)°. In the crystal, intermolecular N—H⋯S interactions link the molecules into a chain along the c axis.

3-(2-Methyl­amino-1,3-thia­zol-4-yl)-2H-chromen-2-one

In the title compound, C13H10N2O2S, the essentially planar 2H-chromene ring system [maximum deviation = 0.0297 (13) Å] and the thiazole ring [maximum deviation = 0.0062 (11) Å] form a dihedral angle of 3.47 (5)°. In the crystal, N—H⋯N and C—H⋯O hydrogen bonds link the molecules into two-dimensional networks parallel to the bc plane. C—H⋯π and π–π [centroid–centroid separation = 3.6796 (8) Å] interactions further stabilize the crystal structure.

2-(4-Fluoro­phen­yl)-2-oxoethyl 3-(trifluoro­meth­yl)benzoate

In the title compound, C16H10F4O3, the fluoroform group is disordered over two orientations with an occupancy ratio of 0.834 (4):0.166 (4). The dihedral angle between the two aromatic rings is 20.34 (9)°. In the crystal, C—H⋯O hydrogen bonds link the molecules into layers lying parallel to the bc plane.

The effect of the fused-ring substituent on anthracene chalcones: crystal structural and DFT studies of 1-(anthracen-9-yl)-3-(naphthalen-2-yl)prop-2-en-1-one and 1-(anthracen-9-yl)-3-(pyren-1-yl)prop-2-en-1-one

Two new anthracene chalcones, namely 1-(anthracen-9-yl)-3-(naphthalen-2-yl)prop-2-en-1-one and 1-(anthracen-9-yl)-3-(pyren-1-yl)prop-2-en-1-one, have been successfully synthesized and the effect of the different fused ring substituent system attached to the anthracene chalcone derivative investigated. These compounds show a very narrow band gap due to the large p-conjugated systems, making them promising candidates as optoelectronic materials. Hirshfeld surface analysis has been carried out to show the contribution of intermolecular contacts and weak interactions to supramolecular stabilization.