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The title compound, C10H8BrN3OS2, a brominated dithiocarbazate imine derivative, was obtained from the condensation reaction of S-methyldithiocarbazate (SMDTC) and 5-bromoisatin. The essentially planar molecule exhibits a Z configuration, with the dithiocarbazate and 5-bromoisatin fragments located on the same sides of the C=N azomethine bond, which allows for the formation of an intramolecular N—H...Ob (b = bromoisatin) hydrogen bond generating an S(6) ring motif. In the crystal, adjacent molecules are linked by pairs of N—H...O hydrogen bonds, forming dimers characterized by an R22(8) loop motif. In the extended structure, molecules are linked into a three-dimensional network by C—H...S and C—H...Br hydrogen bonds, C—Br...S halogen bonds and aromatic π–π stacking.

The title compound, C16H12FN3OS, a fluorinated dithiocarbazate imine derivative, was synthesized by the one-pot, multi-component condensation reaction of hydrazine hydrate, carbon disulfide, 4-fluorobenzyl chloride and isatin. The compound demonstrates near-planarity across much of the molecule in the solid state and a Z configuration for the azomethine C=N bond. The Z form is further stabilized by the presence of an intramolecular N—H...O hydrogen bond. In the extended structure, molecules are linked into dimers by N—H...O hydrogen bonds and further connected into chains along either [2\overline{1}0] or [100] by weak C—H...S and C—H...F hydrogen bonds, which further link into corrugated sheets and in combination form the overall three-dimensional network.

The title compound, C17H15N3OS2 was obtained from the condensation reaction of S-benzyldithiocarbazate and 5-methylisatin. In the solid-state, the molecule adopts a Z configuration with the 5-methylisatin and dithiocarbazate groups located on the same side of the C=N bond, involving an intramolecular N—H...O hydrogen bond.

This paper intentions to study the effect of using different tapered longitudinal section manifolds rather than the uniform one, in a Z shaped flat plate solar collector on; the uniformity of flow distribution, pressure drop, and consequently temperature profile. To this end, a 3D CFD model is planned to mimic a parallel piping network of Z configuration. Considering both fluid and piping body domains, and moreover, the inlet and outlet junctions, that would affect the resulted system pressure drop. The system has the following specifications: uniform header diameter of 20 mm, manifold and header lengths of 1150 mm, ten tubes, tubes diameter of 7 mm, tubes length of 1780 mm, horizontally mounted, and, with imposed solar radiation. Different taper ratios of the manifold, from 1.0 to 2.4 are studied against inlet ReD ranges from 300 to 2100. The model is validated with existing experimental outcomes from literature and showed an excellent agreement. Two indices are used to quantify the flow distribution uniformity. Generally the results concluded that, for enhanced flow distribution uniformity, an optimum taper ratio is important to be defined per each ReD.

The title compound, C11H9NO3, contains an isoxazole and a hydroxybenzylidene ring, which are inclined to each another by 3.18 (8)°. There is an intramolecular C—H...O contact forming an S(7) ring. In the crystal, molecules stack head-to-tail in columns along the b-axis direction, linked by offset π–π interactions [intercentroid distances of 3.676 (1) and 3.723 (1) Å]. The columns are linked by O—H...O and O—H...N hydrogen bonds, forming layers parallel to the ab plane. The layers are linked by C—H...O hydrogen bonds, forming a supramolecular three-dimensional framework. An analysis of the Hirshfeld surfaces points to the importance of the O—H...O and O—H...N hydrogen bonding in the packing mechanism of the crystal structure.

The title compound, C11H9NO3, contains an isoxazole and a hydroxybenzylidene ring, which are inclined to each another by 3.18 (8)Å. There is an intramolecular C-H...O contact forming an S(7) ring. In the crystal, molecules stack head-to-tail in columns along the b-axis direction, linked by offset π-π interactions [intercentroid distances of 3.676 (1) and 3.723 (1) Å ]. The columns are linked by O-H...O and O-H...N hydrogen bonds, forming layers parallel to the ab plane. The layers are linked by C-H...O hydrogen bonds, forming a supramolecular three-dimensional framework. An analysis of the Hirshfeld surfaces points to the importance of the O-H...O and O-H...N hydrogen bonding in the packing mechanism of the crystal structure. [ABSTRACT FROM AUTHOR]

Esters of 3-alkyl-4-oxo-2-butenoic acid, which are very important synthons, are not equally accessible in both E and Z configurations. The (Z)-isomers can be easily obtained from 3-alkyl-4-hydroxybutenolides, in turn prepared by aminoalkylation of aliphatic aldehydes with glyoxylic acid. The (E)-isomers, on the contrary, result from laborious procedures: the condensation of aldehydes with glyoxylic acid, followed by separation from γ -hydroxybutenolide by-product and esterification, or of aldehyde enamines with glyoxylic esters, followed by Z ester by-product conversion into γ -aminobutenolide and purification. Here, we describe a straightforward route to the title compounds, applied to methyl (E)-3-propyl-4-oxo-2-butenoate, avoiding any problematic by-product or isomer chromatographic separation: pentanal and glyoxylic acid are condensed to 3-propyl-4-hydroxybutenolide, which is converted to methyl (Z)-3-propyl-4-oxo-2-butenoate and then isomerized to E ester under acidic conditions. [ABSTRACT FROM AUTHOR]

Abstract: [1,2a]Benzimidazol-2-yl amidine was synthesized by adding cyclopentanamine to iminoester in ethanol. The structure of amidine 1 was characterized by IR, 1H NMR, 1H–1H NOESY, 13C NMR, DEPT, XHCOR spectra, thermogravimetric analysis (TGA), differential thermal analysis (DTA), differential scanning calorimetry thermograms (DSC), elementary analysis as well as by X-ray diffraction. The single crystals suitable for X-ray measurement were obtained by recrystallization at room temperature. The amidine group of a model was found to have Z configuration in the crystal. This compound crystallizes in a P21/n monoclinic unit cell with parameters a =12.679(2)Å, b =8.468(3)Å, c =13.108(2)Å, β =96.538(2)°, V =1398.2Å3 and Z=4. [Copyright &y& Elsevier]