Can we trust the experiment? Anisotropic displacement parameters in 1-(halomethyl)-3-nitrobenzene (halogen = Cl or Br)

1-(Chloromethyl)-3-nitrobenzene, C7H6NClO2, and 1-(bromomethyl)-3-nitrobenzene, C7H6NBrO2, were chosen as test compounds for benchmarking anisotropic displacement parameters (ADPs) calculated from first principles in the harmonic approximation. Crystals of these compounds are isomorphous, and theory predicted similar ADPs for both. In-house diffraction experiments with Mo Kα radiation were in apparent contradiction to this theoretical result, with experimentally observed ADPs significantly larger for the bromo derivative. In contrast, the experimental and theoretical ADPs for the lighter congener matched reasonably well. As all usual quality indicators for both sets of experimental data were satisfactory, complementary diffraction experiments were performed at a synchrotron beamline with shorter wavelength. Refinements based on these intensity data gave very similar ADPs for both compounds and were thus in agreement with the earlier in-house results for the chloro derivative and the predictions of theory. We speculate that strong absorption by the heavy halogen may be the reason for the observed discrepancy.

On the reactivity of P-chloro dithieno[3,2-b:2′,3′-d]phosphole oxide

The P-functionalization of dithieno[3,2-b:2′,3′-d]phosphole oxides via reaction of a P-chloro derivative with aromatic amines and alcohols is reported. The reactions proceed rapidly and provide the products in good yields, highlighting the synthetic versatility of the P-chloro dithienophosphole oxide toward effectively modifying the molecular scaffold without the need for elaborate phosphorus precursor syntheses. The resulting phosphinic amide and ester products show interesting photophysics that strongly depend on the nature of the P-substituent such as high luminescence quantum yields for the ester derivatives, as well as aggregation-induced enhanced emission for the amide derivative. The phosphinic amide species also shows intriguing self-assembly in the solid state via hydrogen bonding.

Antioxidant Activity of Carvone and Derivatives against Superoxide Ion

Carvone has corroborated its versatility as starting material for building blocks synthesis in organic chemistry, being achieved a new chiral lactone. It has been done a study on the antioxidant activity against superoxide of carvone and a chloro derivative that show the potent activity of the natural product ( R)-carvone, 1.

Some Conventional and Convenient Process for Functionalization of 6-Phenyl-4,5-Dihydropyridazinone Compounds

The pyridazinone derivatives, particularly those bearing substituted different group or atom at a different position, have attracted considerable attention due to their characteristic pharmacological and other anticipated activities. These activities promoted the synthesis of a large number of substituted pyridazinone derivatives in order to explore the usefulness of this heterocyclic system. In the present review, various synthetic methods have been studied for the synthesis of substituted pyridazinone derivatives. The behaviour of the pyridazinone toward formaldehyde/piperidine, ethyl chloroacetate, chloroacetic acid, benzene sulfonyl chloride, bromine/acetic acid and aromatic aldehydes has also been studied. However, the reactions of the chloro derivative resulting from the reaction of pyridazinone with phosphorus oxychloride (POCl₃). The behavior of chloropyridazine toward hydrazines, thiourea, sodium azide, anthranilic acid, aromatic amines and sulfa compounds have also been taken into consideration. Thethiopyridazinone derivativeswere prepared from the reaction of pyridazinone with phosphorus pentasulphide (P₂S₅). All the structures of were established on the based of spectroscopic data.<p> </p><p><strong> </strong></p>

Flotation of copper-bearing carbonaceous shale in the presence of amine type frothers

<p>Hexylamine, chloro-derivative of propylamine, and ammonium chloride were used for flotation of Permian carbonaceous copper bearing shale from the Legnica-Glogow Copper Basin region in SW Poland. It was confirmed that naturally hydrophobic shale, known as Kupferschiefer, can be made floatable by application of short chain amines as frothers. It was also established that the short chain amine chloro-derivatives as well as salmiac, the first member of the amine family, can be used as a frother for flotation of the investigated shale sample. It results from the paper that the investigated amine frothers work similarly if the comparison of the flotation results is made using their concentration expressed in relative form taking into account the critical coalescence concentration of the frother.</p>

Crystal structure of 1,6-dithiacyclodeca-cis-3,cis-8-diene (DTCDD)

The title compound, C8H12S2(trivial name DTCDD), was obtained as a side product of the reaction betweencis-1,4-dichlorobut-2-ene and sodium sulfide. The asymmetric unit consists of one-quarter of the molecule (S site symmetry 2) and the complete molecule has 2/m(C2h) point symmetry with the C=C bond in anEconformation. The geometry of the title compound is compared to those of a chloro derivative and a mercury complex.