917 research outputs found
3,4-Dimethyl-N-[(E)-3-nitrobenzylidene]-1,2-oxazol-5-amine
In the title compound, C12H11N3O3, the dihedral angle between the 3-nitrobenzaldehyde and 5-amino-3,4-dimethyl-1,2-oxazole moieties is 2.46 (12)°. The molecule is close to planar, the r.m.s. deviation for the non-H atoms being 0.028 Å. The packing only features van der Waals interactions between the molecules
(2E)-3-[4-(Dimethylamino)phenyl]-1-(2,5-dimethyl-3-thienyl)prop-2-en-1-one
The asymmetric unit of the title compound, C17H19NOS, contains two independent molecules which differ in the dihedral angles between the five- and six-membered rings [12.52 (10) and 4.63 (11)°]. Weak intermolecular C—H⋯O hydrogen bonds link the two independent molecules into pseudocentrosymmetric dimers. In one molecule, the O atom of the carbonyl group is disordered over two positions in a 0.699 (4):0.301 (4) ratio
N-[(E)-1,3-Benzodioxol-5-ylmethylidene]-3,4-dimethyl-1,2-oxazol-5-amine
In the title compound, C13H12N2O3, the dihedral angle between the aromatic rings is 7.94 (12)°. In the crystal, inversion dimers linked by pairs of C—H⋯O hydrogen bonds generate R
2
2(6) loops. Weak π–π [centroid–centroid separations = 3.7480 (13) and 3.9047 (13) Å] and C—H⋯π interactions help to consolidate the packing
(E)-2-Methyl-6-[(1-phenyl-1H-pyrazol-4-yl)methylidene]cyclohexanone
The asymmetric unit of the title compound, C17H18N2O, contains two independent molecules. In both, the cyclohexane ring adopts a flattened chair conformation, and the 3- and 4-methylene C atoms as well as the methyl C atoms are disordered over two positions, the occupancy of the major component being 68 (1)% in one molecule and 64 (1)% in the other. The phenyl and pyrazole rings in both molecules are approximately coplanar, the r.m.s. deviations being 0.048 and 0.015 Å, respectively. Weak intermolecular C—H⋯O hydrogen bonding is present in the crystal structure
6-Amino-5-(1-amino-2,2-dicyanovinyl)-3,3a,4,5-tetrahydro-2H-indene-4-spiro-1′-cyclopentane-3a,7-dicarbonitrile–thiophene-2-carbaldehyde (1/0.5)
In each of the two independent indene-4-spiropentane molecules in the asymmetric unit of the title 2:1 adduct, C19H18N6·0.5C5H4OS, the cyclohexene ring adopts a half-chair conformation and the cyclopentene and cyclopentane rings adopt envelope conformations. The mean plane through the cyclohexene/cyclopentene fused system is aligned at a dihedral angle of 77.9 (1)° with respect to the mean plane through the cyclopentane ring in one molecule and 87.0 (1)° in the other. In the crystal, adjacent indene-4-spiropentane molecules are linked by N—H⋯N hydrogen bonds into a three-dimensional network. The spaces within the network are occupied by the thiophene-2-carbaldehyde molecules. The thiophene-2-carbaldehyde unit is disordered over two positions of equal occupancy. The crystal studied was found to be a non-morohedral twin with two minor twin components of 18.4 and 9.7%
2,4,5-Trimethoxybenzaldehyde monohydrate
In the title compound, C10H12O4·H2O, the 2,4,5-trimethoxybenzaldehyde molecule is almost planar (rms deviation = 0.0183 Å). There is an R
1
2(5) ring motif due to O—H⋯O hydrogen bonding. In the crystal, the molecules are stabilized in the form of one-dimensional polymeric chains extending along [010] due to O—H⋯O hydrogen bonding with adjacent water molecules. The H atoms involved in intermolecular hydrogen bonding are disordered over two sets of sites of equal occupancy
Metal Organic Frameworks as Versatile Hosts of Au Nanoparticles in Heterogeneous Catalysis
[EN] The present review describes the state of the art of the use of metal organic framework (MOF)-encapsulated Au nanoparticles (NPs) as heterogeneous catalysts. The purpose is to show that catalysts with very good performance, frequently among the most active Au catalysts reported so far, can be obtained by incorporation of Au NPs inside MOFs. The available data indicate that the high catalytic activity of MOF-encapsulated Au NPs derives from (i) small particle size, (ii) high dispersion and homogeneous distribution inside MOFs crystals, (iii) stabilization of particle size by confinement of Au NPs inside MOFs cages, and (iv) the synergy that can arise by the combination of the activity of Au NPs and MOFs. After some introductory sections presenting general issues commenting about the relevance of Au catalysis, how to determine the internal versus external location of Au NPs, and evidence in support for catalyst stability, this mini review covers reactions using Au@MOFs as catalysts for oxidations, reductions, tandem processes, and photocatalysis with the emphasis in providing a comparison with the performance of other alternative Au-containing catalysts. In the final section, we summarize in our view the current achievements and which are the next targets in this area.A.D.M. thanks University Grants Commission, New Delhi for the award of Assistant Professorship under its Faculty Recharge Programme. A.D.M. also thanks Department of Science and Technology, India, for the financial support through Fast Track project (SB/FT/CS-166/2013) and the Generalidad Valenciana for financial aid supporting his stay at Valencia through the Prometeo programme. Financial support by the Spanish Ministry of Economy and Competitiveness (CTQ-2015-69153-CO2-R1 and Severo Ochoa) and Generalidad Valenciana (Prometeo 2013-014) is gratefully acknowledged.Dhakshinamoorthy, A.; Asiri, AM.; García Gómez, H. (2017). Metal Organic Frameworks as Versatile Hosts of Au Nanoparticles in Heterogeneous Catalysis. ACS Catalysis. 7(4):2896-2919. https://doi.org/10.1021/acscatal.6b03386S289629197
2-[(4-Chlorobenzylidene)amino]-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile
In the title compound, C16H13ClN2S, the dihedral angle between the 4-chlorobenzaldehyde moiety and the heterocyclic five-membered ring is 7.21 (17)°. In the crystal, molecules are linked by weak C—H⋯π interactions, generating [100] chains
2-[(2-Chlorobenzylidene)amino]-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile
In the title compound, C16H13ClN2S, the mean planes fitted through all non-H atoms of the heterocyclic five-membered and the benzene rings are oriented at a dihedral angle of 5.19 (7)°. In the crystal, a weak C—H⋯π interaction occurs, along with weak π–π interactions [cenroid–centroid distance = 3.7698 (11) Å]
4-[(Anthracen-9-ylmethylidene)amino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one
In the title compound, C26H21N3O, the phenyl ring of the 4-aminoantipyrine group and the heterocyclic five-membered ring along with its substituents, except for the N-bound methyl group (r.m.s. deviation = 0.0027 Å), form a dihedral angle of 54.20 (5)°. Two S(6) ring motifs are formed due to intramolecular C—H⋯N and C—H⋯O hydrogen bonds. In the crystal, molecules are linked into supramolecular chains along the a-axis direction via C—H⋯O contacts
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