RESUMO
The title compound 5,6-O-(4-chlorophenyl)-L-ascorbic acid (C13H11ClO6) was synthesized using nanosolid superacid SO2-4/SnO2 as a catalyst and its structure was characterized by IR, 1H NMR and single-crystal X-ray diffraction. 1H NMR data indicated the product is a mixture of two diastereomer compounds (a(7S) and b(7R)). And the crystal of one diastereomer compound a(7S) belongs to orthorhombic system, space group P212121 with a = 6.501(4), b = 7.803(5), c = 25.013(15) Å, V 1268.7(13) Å3, Z = 4, Dc 1.564g/cm3, µ(Mo-Kα) = 0.325 mm-1, F(000) = 616, R = 0.0255 and wR(I > 2σ (I)) = 0.0624. X-ray crystal structure data display that the hydrogen bonding interactions observed link the molecules to form a three-dimensional system. In addition, 5,6-O-(4-chlorophenyl)-L-ascorbic acid (CPAA) exhibited strong free-radical scavenging activities in vitro against 2,2-diphenyl-1-picrylhydrazyl and superoxide anion. Therefore, CPAA should be investigated further as a worthy antioxidant.
RESUMO
A series of novel sodium (5-methyl-2-alkyl-1,3-dioxane-5-yl) carboxylate surfactants were synthesized using nanosolid superacid SO4²â»/Fe2O3as a catalyst and characterized by ¹H NMR, IR and elemental analysis. The critical micelle concentration (CMC) of surfactants was determined and the results showed that the CMC values were less than 2.0 x 10⻳ mol/L. Other relevant surface properties (Krafft point, emulsion stability, foam ability, degradability) were also evaluated. It was suggested that with respect to emulsion formation, foam stability and the range of application temperature, compared with traditional surfactants, the new surfactants could give better results and showed better properties when used as an emulsifier in emulsion polymerization. In addition, the surfactants were stable under neutral and alkaline conditions, and could form solid under acid condition. The solid will generate the original surfactants for reuse with alkali. Sodium (5-methyl-2-alkyl-1,3-dioxane-5-yl) carboxylate is likely to be a new type of 'environmentally friendly' surfactant.
RESUMO
A new chiral 1,3-dioxane compound was synthesized by aldol condensation reaction in this paper. The reaction of cinnamic aldehyde with 2.1 equiv. of 2,2-bis(hydroxymethyl) butanol in N,N-dimethylformamide and cyclohexane, nanosolid superacid SO4(2-)/Fe2O3 was applied as catalyst, afforded the new chiral 1,3-dioxane compound (E)-(5-ethyl-2-styryl-1,3-dioxan-5-yl) methanol. The compound was fully characterized with infrared spectra, elemental analysis, melting points, 1H NMR and X-ray diffraction. Single crystal X-ray diffraction analysis revealed that the compound crystallized in the monoclinic system, space group P2(1) with a = 5.717(2) Å, b = 11.684(4) Å, c = 10.569(4) Å, α = 90.00 degrees, ß = 99.646(4) degrees, γ = 90.00 degrees, V = 696.0(4) Å3, Z = 2, Dc = 1.185 g/cm(-3), R = 0.0182, µ = 0.081 mm(-1), F(000) = 268. In addition, the antibacterial activities of the compound against Bacillus subtilis, Escherichia coli and Staphylococcus aureus have been investigated.
RESUMO
In the title compound, {[NiWO(4)(C(16)H(36)N(4))]·4H(2)O}(n), the Ni(II) ion lies on an inversion center and is octahedrally coordinated by four N atoms of the tetradentate macrocyclic 5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-decane (L) ligand in the equatorial plane and two O atoms of [WO(4)](2-) anions in axial positions. Each [WO(4)](2-) anion bridges two adjacent [NiL](2+) cations, forming a chain along [001]. The chains are further connected via N-Hâ¯O, O-Hâ¯O and C-Hâ¯O hydrogen-bonding inter-actions, generating a three-dimensional structure.
RESUMO
In the title compound, C(12)H(13)ClO(4), the 1,3-dioxane ring adopts a chair conformation and the 2-chloro-benzene and methyl substituents occupy equatorial sites. The carboxyl group is in an axial inclination. In the crystal, carb-oxy-lic acid inversion dimers linked by pairs of O-Hâ¯O hydrogen bonds generate R(2) (2)(8) loops.
RESUMO
In the title compound, C(12)H(24)O(4), the dioxane ring adopts a chair conformation; the n-hexyl chain, which occupies an equatorial position, has an extended zigzag conformation. In the crystal, mol-ecules are connected by O-Hâ¯O hydrogen-bonds into a zigzag chain running along the b axis, giving rise to a herringbone pattern.
RESUMO
In the title compound, C(13)H(26)O(4), the dioxane rings adopts a chair conformation; the n-heptyl chain occupies an equatorial position. In the crystal, mol-ecules are connected by O-Hâ¯O hydrogen bonds into a zigzag chain running along the a axis, giving rise to a herringbone pattern. There are two independent mol-ecules in the asymmetric unit.
RESUMO
THE CHIRAL TITLE COMPOUND [SYSTEMATIC NAME: 4-(1-methyl-vinyl)cyclo-hexene-1-carbaldehyde oxime], C(10)H(15)NO, crystallizes with two mol-ecules in the asymmetric unit, one of which shows disorder of its propenyl substituent over two sets of sites in a 50:50 ratio. In both mol-ecules, the six-membered carbaldehyde oxime ring adopts an approximate envelope conformation in which the C atom bearing the propenyl substituent represents the flap position. In both mol-ecules, the plane passing through the propenyl substituent is nearly perpendicular to the mean plane of the six-membered ring [dihedral angles = 84.6â (6) and 87.4â (3)°]. In the crystal, the two independent mol-ecules are linked by a pair O-Hâ¯N hydrogen bonds across a pseudo-inversion centre, generating a dimer. The unit cell of the known racemate of the title compound is similar to the cell found here, but with space group P.
RESUMO
The four six-membered rings all adopt chair conformations in the two independent mol-ecules of the title cyclo-hexa-none cyclic diacetal with penta-erythritol, C(17)H(28)O(4).
RESUMO
The title compound, C(25)H(26)O(2), crystallizes with two crystallographically independent mol-ecules in the asymmetric unit. The differences between the two mol-ecules are marginal. The three benzene rings of each mol-ecule are in a propeller orientation and the 1,3-dioxane ring adopts a chair conformation.
RESUMO
The title compound, [Ni(C(8)H(5)O(4))(C(16)H(36)N(4))]ClO(4)·H(2)O, has the Ni(II) atom in a distorted octa-hedral geometry, surrounded by coordination by four N atoms of the 5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-azacyclo-tetra-decane ligand in a folded configuration, and two carboxyl-ate O atoms of the 2-carboxy-benzoate ligand in cis positions. The complex cation, the disordered perchlorate anion [occupancies 0.639â (8):0.361â (8)] and uncoordinated water mol-ecules engage in N-Hâ¯O and O-Hâ¯O hydrogen bonding, forming a layer structure parallel to (010).
RESUMO
In the title compound, [Ag(2)(C(6)H(6)NO(3)S)(2)(C(10)H(8)N(2))(2)](n), the Ag(I) atom is four-coordinated by two N atoms from two symmetry-related 4,4'-bipyridine (bipy) and two O atoms from two independent 4-amino-benzene-sulfonate (ABS) ligands. The two inter-chain Ag(I) atoms are bridged by two independent ABS ligands through weak Ag-O bonds and Agâ¯Ag attractions, forming a ladder-like chain coordination polymer [Ag(2)(ABS)(2)(bipy)(2)](n) parallel to [001], which is further linked to generate a two-dimensional structure via N-Hâ¯O hydrogen-bonding inter-actions.
RESUMO
In the title compound, [Ni(C(7)H(5)O(2))(C(16)H(36)N(4))]ClO(4)·C(7)H(6)O(2), the Ni atom displays a distorted octa-hedral coordination geometry with four N atoms of the ligand rac-5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-azacyclo-tetra-decane (L) in a folded configuration and two benzoate (bz) O atoms. The [Ni(rac-L)(bz)](+) complex cation, perchlorate anion and benzoic acid mol-ecules engage in hydrogen bonding, with Nâ¯O distances between 2.970â (3) and 3.123â (3)â Å and an Oâ¯O distance of 2.691â (3)â Å.
RESUMO
In the title compound, C(26)H(26)O(4), steric crowding of the Ph(3)C- group with the -CH(CO(2)Et)(2) unit leads to a long C-C bond [1.585â (2)â Å]. One of the two ethyl groups is disordered over two sites in a 60:40 ratio.
RESUMO
The Ni atom in the title salt, [Ni(C(7)H(5)O(2))(C(16)H(36)N(4))]ClO(4)·H(2)O, is in a six-coordinate octa-hedral geometry. The metal atom is chelated by the carboxyl-ate group, and the macrocyclic ligand adopts a folded configuration. The cation, anion and water mol-ecules engage in hydrogen bonding to form a layer structure.
RESUMO
In the title compound, C(12)H(16)O(4), the 1,3-dioxane ring adopts a chair conformation; the 2-phenyl substitutent occupies an equatorial position. Adjacent mol-ecules are linked by O-Hâ¯O hydrogen bonds into a chain.