Guangliang Song

9-Butyl-9H-carbazole

The title compound, C16H17N, is a carbazole derivative that has been designed and synthesized as a potential organic electronic device, such as an OLED. The tricyclic aromatic ring system is essentially planar, the two outer rings making a dihedral angle of 4.8 (1)°. No classical hydrogen bonds are observed in the crystal structure.

Enhancement of catalytic activity by homo-dispersing S 2 O 8 2– -Fe 2 O 3 nanoparticles on SBA-15 through ultrasonic adsorption

Abstract Mesoporous superacids S2O82–-Fe2O3/SBA-15 (SFS) with active nanoparticles are prepared by ultrasonic adsorption method. This method is adopted to ensure a homo-dispersed nanoparticle active phase, large specific surface area and many acidic sites. Compared with bulk S2O82–-Fe2O3, Bronsted acid catalysts and other reported catalysts, SFS with an Fe2O3 loading of 30% (SFS-30) exhibits an outstanding activity in the probe reaction of alcoholysis of styrene oxide by methanol with 100% yield. Moreover, SFS-30 also shows a more excellent catalytic performance than bulk S2O82–-Fe2O3 towards the alcoholysis of other ROHs (R = C2H5-C4H9). Lewis and Bronsted acid sites on the SFS-30 surfaces are confirmed by pyridine adsorbed infrared spectra. The highly efficient catalytic activity of SFS-30 may be attributed to the synergistic effect from the nano-effect of S2O82–-Fe2O3 nanoparticles and the mesostructure of SBA-15. Finally, SFS-30 shows a good catalytic reusability, providing an 84.1% yield after seven catalytic cycles.

2,5-Dibromo­terephthalic acid dihydrate

The asymmetric unit of the title compound, C8H4Br2O4·2H2O, contains one half-molecule of 2,5-dibromoterephthalic acid (DBTA) and one water molecule. The DBTA molecule is centrosymmetric. In the crystal structure, intermolecular O—H⋯O hydrogen bonds link the molecules, forming a three-dimensional framework.

2-(4-Methyl­benzo­yl)benzoic acid monohydrate

In the title compound, C15H12O3·H2O, the two rings are oriented at a dihedral angle of 69.12 (3)°. In the crystal structure, intermolecular O—H⋯O hydrogen bonds link the molecules into a three-dimensional framework.

Hexaethyl­guanidinium chloride

The title compound, C13H30N3+·Cl−, is a phase-transfer catalyst. The geometry at the central C atom of the guanidinium cation, which lies on a twofold rotation axis, is almost ideal trigonal planar, with N—C—N angles of 119.8 (2) and 120.08 (11)°. The chloride anion also lies on a twofold rotation axis.

1,4-Di-bromo-2,5-di-p-toluoyl-benzene.

In the title compound, C22H16Br2O2, which has approximate non-crystallographic inversion symmetry, the dihedral angles between the central ring and the pendant rings are 89.1 (4) and 82.4 (3)°; the dihedral angle between the pendant rings is 12.1 (4)°. In the crystal, the packing is influenced by van der Waals forces and no aromatic π–π stacking is observed.

2-Bromo-1-mesitylethanone.

In the molecule of the title compound, C11H13BrO, the adjacent C atoms are almost coplanar with the aromatic ring [maximum deviation 0.035 (3) Å]. In the crystal structure, weak intermolecular C—H⋯O interactions link the molecules into chains along the b axis. A very weak C—H⋯π interaction is also present.

(4,6-Dibromo-m-phenyl-enedimethyl-idyne) tetra-acetate.

The title molecule, C16H16Br2O8, lies on a crystallographic twofold axis. Weak intramolecular C—H⋯O hydrogen bonds may, in part, control the conformation of the molecule. In the crystal structure, molecules are connected into a two-dimensional network via weak intermolecular C—H⋯O hydrogen bonds.