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An efficient three‐component synthesis of 4‐aryl‐2‐aminothiazoles was reported. Phenyl‐thioureas reacted with 2‐bromoacetophenones to form 4‐aryl‐2‐aminothiazoles through cyclization, and the subsequent C−N bonding with benzyl/allyl bromides gave the desired disubstituted thiazoles smoothly. The protocol features transition‐metal free, short reaction time, easily available starting materials, good yields and broad substrate scope, showing potential synthetic value for the synthesis of a variety of biologically or pharmaceutically active compounds. [ABSTRACT FROM AUTHOR]

The hydrothermal reaction of two new tetradentate ligands with different metal salts of cadmium nitrate, zinc chloride, cobalt nitrate and deprotonated terephthalic acid (H2tp), isophthalic acid (H2ip), 4,4′-oxybisbenzoic acid (H2obba) in H2O/DMF or H2O/methanol gave three metal–organic frameworks (MOFs): {[Zn2(L1)(tp)(formate)2]·H2O}n (1), {[Cd2(L2)(ip)2]·2H2O}n (2), {[Co2(L2)(obba)2]}n (3) (L1 = 1,2-bis {2,6-bis [(1H-imidazol-1-yl) methyl]-4-methylphenoxy} ethane, L2 = 1,3-bis {2,6-bis [(1H-imidazol-1-yl) methyl]-4-methylphenoxy} propane). The structures of the frameworks are established by single-crystal X-ray diffraction. Compound 1 is a three-dimensional (3D) framework with a 2-fold interpenetrated form, which exhibits a 2-nodal (3,4)-connected fsh-3,4-P21/c net with a {83}2{85·10} topology. Compound 2 has a 2-nodal (4,8)-connected 3D framework where the dinuclear cadmium cluster secondary building units (SBUs) assemble with isophthalate and ligand L2 to construct a rare topological type sqc22 net with a {32·54}{34·44·510·610} topology. Whereas, Compound 3 can be extended to a 2D interlocked (4,4)-connected 4,4 L28 net with the point symbol {4·64·8}2{42·64}. L1 and L2 are tetradentate ligands with diverse linkers and display different coordination modes. In addition, the thermal stability and photochemical properties of the frameworks are also investigated. [ABSTRACT FROM AUTHOR]

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, C18H17Br2N2+·PF6−, four F atoms of the hexa­fluoro­phosphate anion are disordered. The hexa­fluoro­phosphate ions are linked to 1-benzyl-3-[4-(dibromo­meth­yl)benz­yl]imidazolium cations by C—H⋯F hydrogen bonds, which may be effective in the stabilization of the crystal structure. [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]

The title compound, C10H7NO2, crystallizes with three molecules in the asymmetric unit; these are linked by O—H...N hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title molecule, C21H16N2O, the anthracene ring system is slightly twisted with a dihedral angle of 1.22 (1)° between the two outermost rings. The anthracene mean plane and pyridine ring make a dihedral angle of 72.6 (1)°. The π...π interactions [3.551 (2) Å] between the anthracene fragments form stacks of molecules parallel to the b axis. [ABSTRACT FROM AUTHOR]

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]

Effective CO 2 transformations hold essential significance for carbon neutrality and sustainable energy development. Carboxylative cyclization of propargylic amines with CO 2 serves as an atom-economic reaction to afford oxazolidinones, showing broad applications in organic synthesis and pharmaceutical fields. However, most catalysts involved noble metals, exhibited low efficiency, or required large amounts of base. Hence, it is imperative to explore alternative noble-metal-free catalysts in order to achieve efficient conversion while minimizing the use of additives. Herein, a novel nanopore-based Cu(II)-organic framework ( 1 ) based on a new imidazole carboxylic ligand was successfully constructed and exhibited excellent stability. Catalytic investigations revealed that the combination of 1 with 1,4-diaza[2.2.2]bicyclooctane (DABCO) efficiently catalyzed the carboxylative cyclization of propargylic amines with CO 2 , achieving turnover numbers of 142 based on the catalyst and 7.1 based on DABCO. 1 as a heterogeneous catalyst maintained high catalytic performance even after being reused at least 5 cycles, with its structure remaining stable. The strong activation of Cu(II) cluster nodes of catalyst 1 toward -NH- groups within organic substrates, as demonstrated by mechanism experiments, along with excellent CO 2 adsorption performance and the presence of regular 1D channels, synergistically facilitates the reaction rate. This research presents the first instance of a Cu(II)-organic framework achieving this cyclization reaction, offering wide prospects for novel catalyst design and CO 2 utilization.

Efficient and multiple CO 2 utilization into high-value-added chemicals holds significant importance in carbon neutrality and industry production. However, most catalysis systems generally exhibit only one type of CO 2 transformation with the efficiency to be improved. The restricted abundance of active catalytic sites or an inefficient utilization rate of these sites results in the constraint. Consequently, we designed and constructed two metal hydrogen-bonded organic frameworks (M-HOFs) {[M 3 (L 3- ) 2 (H 2 O) 10 ]·2H 2 O} n (M = Co ( 1 ), Ni ( 2 ); L = 1-(4-carboxyphenyl)-1 H -pyrazole-3,5-dicarboxylic acid) in this research. 1 and 2 are well-characterized, and both show excellent stability. The networks connected by multiple hydrogen bonds enhance the structural flexibility and create accessible Lewis acidic sites, promoting interactions between the substrates and catalytic centers. This enhancement facilitates efficient catalysis for two types of CO 2 transformations, encompassing both cycloaddition reactions with epoxides and aziridines to afford cyclic carbonates and oxazolidinones. The catalytic activities (TON/TOF) are superior compared with those of most other catalysts. These heterogeneous catalysts still exhibited high performance after being reused several times. Mechanistic studies indicated intense interactions between the metal sites and substrates, demonstrating the reason for efficient catalysis. This marks the first instance on M-HOFs efficiently catalyzing two types of CO 2 conversions, finding important significance for catalyst design and CO 2 utilization.

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 title compound, C(24)H(19)N(3)O, the pyrazoline ring adopts an envelope conformation with the C atom linking to the pyridine ring as the flap. The mean plane of the pyrazoline ring makes dihedral angles of 85.54 (4) and 81.66 (3)° with the pyridine ring and the anthracene ring system, respectively. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds. In addition, weak π-π inter-actions [centroid-centroid distances = 3.695 (3)-3.850 (7) Å] are observed.

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.

The title compound, C(20)H(18)N(2)O, which crystallizes with two independent mol-ecules (A and B) in the asymmetric unit, is composed of three aromatic rings (I, II and III). The conformation of the two independent mol-ecules is slightly different. The dihedral angles between the central aromatic ring II and rings I and III are 47.13 (9) and 89.36 (9)°, respectively, for mol-ecule A, and 29.60 (9) and 70.72 (9)°, respectively, for mol-ecule B. Rings I and III are inclined to one another by 86.57 (9)° in mol-ecule A, and 64.59 (10)° in mol-ecule B. The mol-ecular structures are stabilized by intra-molecular N-H⋯O hydrogen bonds. In the crystal structure, mol-ecules are linked through inter-molecular N-H⋯O hydrogen bonds, forming chains propagating in the [010] direction. In addition, a number of C-H⋯π inter-actions are observed.

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(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.