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Enantioselective Michael addition of oxazolones to in situ generated vinylogous imine intermediates is reported. A series of optically active 3-alkylindole derivatives with adjacent quaternary and tertiary stereocenters was obtained. The resulting adducts can readily be converted into syn-configured α,β-disubstituted tryptophan derivatives without compromising the stereoselectivities. [ABSTRACT FROM AUTHOR]

An organocatalytic asymmetric vinylogous Michael addition of dicyanoolefins to vinylogous imine intermediates generated in situ from arenesulfonylalkylindoles has been developed. This protocol provides an easy and convenient approach to C-3 alkyl-substituted indole derivatives with high yields (up to 93%), diastereomeric ratios (up to 99:1 dr) and enantioselectivities (up to 99% ee). The resulting adducts can be also readily converted to pyrazolo derivatives or α-alkylation products of ketones without any decrease of the diastereoselectivities and enantioselectivities. [ABSTRACT FROM AUTHOR]

In the title compound, C22H22O4, the anthracene ring system is slightly non-planar. The two carboxyl­ate groups are both twisted away from the plane of the anthracene ring system by ca. 30°. The crystal packing is stabilized by C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, C18H14N4O2·C2H6OS, the N, N′-di-2-pyridylbenzene-1,3-dicarboxamide mol­ecule is non-planar, the two pyridine rings being twisted with respect to the benzene ring by 30.0 (2) and 27.5 (1)°. The two imino groups are hydrogen bonded with the dimethyl sulfoxide solvent mol­ecule. [ABSTRACT FROM AUTHOR]

The title compound, C26H22N2O4, crystallizes in an anti-C=O orientation, with the two N-substituted benzene rings in different conformations relative to the naphthalene ring. These conformations allow two strong N—H⋯O hydrogen bonds and one C—H⋯π inter­action to generate mol­ecular chains in the cell. [ABSTRACT FROM AUTHOR]

Abstract: Electromagnetic functionalized polyaniline/BaFe12O19 composites were synthesized by in situ polymerization of aniline in the presence of BaFe12O19 particles. The structure and morphologies of products were characterized by X-ray diffraction, infrared spectra, scanning electron microscopy and transmission electron microscopy. In the electromagnetic measurements, it was found that the ac conductivity of BaFe12O19 particles enhanced while the saturation magnetization and coercivity decreased after polyaniline coating. [Copyright &y& Elsevier]

In the title compound, C26H30N2O6, the anthraquinone ring system is not planar, the dihedral angle between the two benzene rings being 11.18 (13)°. The crystal structure is stabilized by C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

An open-frame aluminophosphate, K[(Zn 0.5 Al 0.5 ) 2 P 2 O 8 ] (KZAPO), was rationally designed by a substitution design strategy and synthesized by a high-temperature molten salt method. Compared with the parent crystal of K[ZnBP 2 O 8 ], KZAPO was characterized by similar 4 × 8 × 8 networks, a comparable short-wave ultraviolet transparency and a more regular tetrahedral frame with the mixing of (ZnO 4 ) 6- and (AlO 4 ) 5- anionic groups, highlighting the multifunctional roles that anionic group mixing played in structural and property modulations. In particular, KZAPO was characterized by a high thermal stability (over 850 °C) and a congruent-melting behavior, being conducive to practical applications.

In the cation of the title compound, C(23)H(25)N(4)O(+)·PF(6) (-), the imidazolium ring make dihedral angles of 87.20 (6) and 79.89 (5)° with the pyridine ring and the quinoline system, respectively. In the crystal, C-H⋯F and C-H⋯N hydrogen bonds are observed.

The title silver N-heterocyclic carbene compound, [Ag(C(17)H(16)N(2))(2)]PF(6), crystallizes as a mononuclear salt. The two imidazole rings, which are almost coplanar [maximum deviation from the least squares plane of 0.05 (2) Å], are linked by the Ag atom with a C-Ag-C angle of 178.60 (9)°. In the crystal, C-H⋯F hydrogen bonds, weak π-π inter-actions [centroid-centroid distances = 3.921 (1) and 3.813 (3) Å] and C-H⋯π inter-actions lead to a supermolecular structure.

The title N-heterocyclic carbene compound, C(21)H(22)N(4) (2+)·2PF(6) (-), crystallizes as an inversion twin. There are two independent N-heterocyclic carbene dications (A and B) and four independent hexa-fluoro-phosphate anions in the asymmetric unit. The cations are L-shaped with the benzene rings being inclined to one another by 88.82 (16)° in cation A and 87.03 (16)° in cation B. The imidazole rings make dihedral angles of 35.7 (2) and 32.83 (18)° with the attached benzene rings in cation A, and 30.14 (19) and 31.96 (18)° in cation B. In the crystal, the cations are linked via C-H⋯F hydrogen bonds, forming a three-dimensional network. π-π inter-actions involving the benzene and imidazole rings [centroid-centroid distances = 3.602 (2) and 3.723 (2) Å] and C-H⋯π inter-actions are also present.

The title compound, [Ag(C(27)H(23)BrN(3)O(4))(CH(3)CN)(2)](PF(6))(2), is a mononuclear salt species in which the silver(I) atom is coordinated by one ligand and two acetonitrile mol-ecules and exhibits a distorted T-shaped coordination. The asymmetric unit contains one independent cation and two independent hexa-fluorido-phosphate anions, one of which is disordered over two positions in a 0.756 (11):0.244 (11) ratio. Weak π-π inter-actions between the anthraquinone ring systems [centroid-centroid distance = 3.676 (3) Å], inter-molecular Ag-π inter-actions [Cg⋯Ag = 3.405 Å] and C-H⋯π inter-actions between pairs of adjacent mol-ecules are observed.

In the title salt, C(18)H(19)N(4)O(+)·PF(6) (-), the dihedral angle between the benzimidazolium and benzimidazole ring systems is 16.24 (2)°. In the cation, a π-π inter-action is observed between the imidazolium ring and the benzene ring of the benzimidazole ring system [centroid-centroid distance = 3.5713 (11) Å]. The PF(6) (-) ion is disordered over two sites, with occupancies of 0.895 (2) and 0.105 (2). In the crystal structure, pairs of N-H⋯N hydrogen bonds link the cations, forming centrosymmetric dimers. The dimers are linked via π-π inter-actions [centroid-centroid distance = 3.5606 (11) Å]. In addition, C-H⋯F hydrogen bonds are observed.

In the title compound, C(26)H(18)N(4)O(6), the amide units are approximately coplanar with the benzene ring bonded to the N atom [dihedral angles of 10.59 (10) and 24.00 (12)°], but twisted significantly out of the plane of the benzene ring bonded to the carbonyl C atom [dihedral angles of 57.82 (9) and 58.05 (9)°]. The dihedral angle between the two rings of the biphenyl unit is 77.66 (4)°. Intra-molecular N-H⋯O hydrogen bonds and weak C-H⋯O inter-actions occur. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds and C-H⋯O contacts.

In the title compound, C(20)H(15)N(2)O(+)·Cl(-), the dihedral angle between the fused-ring system and the benzene ring is 63.10 (7)°. In the crystal, N-H⋯Cl hydrogen bonds link the components and aromatic π-π stacking [shortest centroid-centroid distance = 3.6421 (12) Å] occurs.

The title compound, C(23)H(17)N(3), can be used in coordination chemistry. The anthracene ring makes dihedral angles of 86.08 (5) and 76.63 (6)°, respectively, with the pyridine and pyrazole rings. The dihedral angle between the pyrazole and pyrimidine rings is 11.79 (7)°. In the structure, weak inter-molecular C-H⋯N hydrogen bonds are observed.

In the title compound, C(33)H(25)N(2) (+)·PF(6) (-), the naphthalene ring system is twisted with respect to the anthracene and benzene rings, making dihedral angles of 72.40 (3) and 71.39 (4)°, respectively. The crystal structure is stabilized by intermolecular C-H⋯F hydrogen bonding. Four F atoms of the hexa-fluoro-phosphate anion are disordered over two sets of sites in a 0.645 (4):0.355 (4) ratio.