二[1-(2-噻吩基)-4,4,4-三氟丁二酮-1,3]合铜(Ⅱ)及其某些溶剂加合物的热分析研究

Thermoanalysis study has been carried out on the complex of bis[1-(2-thienyl)-4,4,4-trifluoro-butanedione- 1,3]copper(Ⅱ) and its adducts with pyridine, 2,2′-bipyridine, quinoline and dimethyl sulfoxide in a dynamic ni-trogen atmosphere by simultaneous TG-DTG-DSC technique. The experimental results showed that the decomposi-tion modes of the solvent molecules were various according to the different structures of the complex, in general, the decomposition of them was ahead of the decomposition of the ligand 1-(2-thienyl)-4,4,4-triflurobu- tanedione-1,3. Among them the adduct with 2,2-bipyridine showed a quite unique thermal behavior. Several methods have been jointly used to study the kinetics of all the thermal decomposition stages for title compounds, which showed that the evolution of the solvent molecules was controlled mainly by Rn mechanism (or Am mechanism for 2,2-bipyridine adduct) with lower activation energy; while the release of 1-(2-thienyl)-4,4,4-trifluro-butane- dione-1,3 was gove- rned by D2 or D3 mode with higher activation energy.     

The (E)/(Z)-ratio in the reaction of 5-(2-aryl-2-oxoethyl)-2-thioxo-4-oxo-1,3-thiazolidines with bromine

Summary 3-Aryl-, 3-benzyl-, and 3H-5-(2-aryl-2-oxoethyl)-2-thioxo-4-oxo-1,3-thiazolidines3a–h react with bromine in acetic acid solution to give mixtures of the respective 5-aroylmethylene (E) and (Z) diastereomeric derivatives5 and6. They contain more than 85% of the (E)-diastereomers along with some pure isomers. The intermediacy of the 5-bromo derivatives4 is proven and a plausible route of the reaction is presented. Structures of compounds3–6 are evidenced by analytical and spectral data.

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Das Verhältnis von (E)- und (Z)-Isomeren bei der Reaktion von 5-(2-Aryl-2-oxomethyl)-2-thioxo-4-oxo-1,3-thiazolidinen mit Brom

Zusammenfassung 3-Aryl-, 3-Benzyl- und 3H-5-(2-Aryl-2-oxoethyl)-2-thioxo-4-oxo-1,3-thiazolidine3a–h reagieren mit Brom in essigsaurer Lösung zu Gemischen der entsprechenden diastereomeren 5-Arylmethylen-Derivate ((E) und (Z))5 und6. Sie enthalten mehr als 85% des (E)-Diastereomeren. Die intermediäre Natur der 5-Brom-Derivate4 wird bewiesen; ein Reaktionsweg wird vorgeschlagen. Die Strukturen der Verbindungen3–6 werden durch analytische und spektroskopische Daten abgesichert.

     

Fe3O4@TiO2@O2PO2(CH2)NHSO3H as a novel nanomagnetic catalyst: Application to the preparation of 2‐amino‐4,6‐diphenylnicotinonitriles via anomeric‐based oxidation

A new, green and reusable nanomagnetic heterogeneous catalyst, namely Fe₃O₄@TiO₂@O₂PO₂(CH₂)NHSO₃H, was synthesized and fully characterized using suitable techniques such as infrared spectroscopy, X‐ray diffraction, scanning and transmission electron microscopies, thermogravimetry, vibrating sample magnetometry and energy‐dispersive X‐ray spectroscopy. The applicability of the constructed heterogeneous core–shell catalyst as a promoter was successfully explored for the synthesis of 2‐amino‐4,6‐diphenylnicotinonitrile derivatives upon the reaction of a good range of aromatic aldehydes, acetophenone derivatives, malononitrile and ammonium acetate. The desired products were obtained with good to high yields in short reaction times under solvent‐free conditions. The suggested mechanism offers an anomeric‐based oxidation route to the products in the final step of the synthetic pathway.     

KF/Al2O3催化下由芳醛、丙二腈和2-(1,2-二氢-3-亚茚基)丙二腈或2-(2,3-二氢-4H-亚萘基)丙二腈一步合成芴或菲衍生物

以芳醛、丙二腈、2-(1,2-二氢-3-亚茚基)丙二腈或2-(2,3-二氢-4H-亚萘基)丙二腈为原料, 乙醇为溶剂, 在80 ℃下以KF/Al2O3为催化剂合成了一系列芴或菲的衍生物, 该方法具有反应条件温和、产率高(72%～88%)和操作简单等优点. 产物的结构通过IR, 1H NMR和元素分析表征.