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Mitra Ghassemzadeh Mostafa M. Pooramini Maasoomeh Tabatabaee Majid M. Heravi Bernhard Neumüller 《无机化学与普通化学杂志》2004,630(5):625-626
The reaction of 3, 4‐dihydro‐6‐methyl‐3‐thioxo‐1, 2, 4‐triazin‐5(2H)‐one (6‐aza‐2‐thiothymine, AAT, 1 ) with copper(I) chloride in presence of hydrochloric acid in methanol gives the complex [{CuCl2(H2O)2(AT)}2] · 2H2O, 2 , AT = 6‐azathymine) in excellent yield. 2 was characterized by IR spectroscopy and elemental analyses as well as mass spectrometry. Also single‐crystal X‐ray diffraction studies on compound 2 revealed that AT acts as a monodentate ligand in the centrosymmetric binuclear complex via its oxygen atom. Crystal data for 2 at —80 °C: space group P21/c with a = 550.1(1), b = 2712.5(1), c = 729.7(1) pm, β = 95.99(1)°, Z = 2, R1 = 0.0213. 相似文献
65.
Ali Jabbari Masoumeh Hasani Mojtaba Shamsipur 《Journal of inclusion phenomena and macrocyclic chemistry》1993,15(4):329-340
The complexation reactions between Tl+ and Ag+ ions and several crown ethers have been studied conductometrically in acetonitrile, acetone and dimethylformamide solutions at 25°C. The stability constants of the resulting 1:1 complexes were determined, and found to decrease in the order DA18C6>DC18C6>DB30C10>18C6>DB21C7>DB24C8>DB18C6>B15C5 >12C4, in the case of Tl+ complexes, and in the order DA18C6>DC18C6>18C6>DB18C6 >DB24C8>DB30C10B15C5>DB21C7 for Ag+ complexes. There is an inverse relationship between the stabilities of the complexes and the Gutamnn donicity of the solvents. The influence of a number of atoms in the macrocycle and of substituents in the polyether ring on the stability of the complexes is discussed. 相似文献
66.
Ahmad Shaabani Abbas Rahmati Masoumeh Sharifi Jafar Mogimi Rad Behnaz Aghaaliakbari Elham Farhangi Donald G. Lee 《Monatshefte für Chemie / Chemical Monthly》2007,138(7):649-651
Summary. The oxidation of arenes and sulfides by potassium permanganate was accomplished in good yields under solvent free and heterogeneous
conditions when manganese(II) sulfate is used as a solid support. After extraction of the organic products, the inorganic
products can be reoxidized to permanganate. This result is important because it provides an approach to oxidation reactions
that is, in theory, infinitely sustainable. 相似文献
67.
Semicarbazones,1,1-diacetates and acetals are efficiently converted to their corresponding carbonyl compounds using synergistic effect between KBrO3 and MoO3 in refluxing CH3CN-H20 in good to high yields. 相似文献
68.
A simple, low-cost, and effective cooling/heating-assisted headspace solid-phase microextraction (CHA–HS–SPME) device, capable of direct cooling the fiber to low temperatures and simultaneous heating the sample matrix to high temperatures, was fabricated and evaluated. It was able to cool down the commercial and handmade fibers for the effective tapping of volatile and semi-volatile species in the headspace of complex solid matrices, with minimal manipulation compared with conventional SPME. The CHA–HS–SPME system can create large temperature gaps (up to 200 °C) between the fiber and the sample matrix, because the cooling process is directly applied onto the fiber. 相似文献
69.
Masoumeh Pirdadeh-Beiranvand Abbas Afkhami Tayyebeh Madrakian 《Journal of the Iranian Chemical Society》2018,15(7):1527-1534
Resonance light-scattering (RLS) technique was developed for studying the interaction of silver nanoparticles (Ag NPs) with bisphenol A. A simple and environmentally friendly method was developed to synthesize Ag NPs using cinnamon extract. Synthesized nanoparticles were characterized using various measurement techniques. The synthesized Ag NPs were nearly spherical, with the sizes ranging from 30 to 60 nm. Spectral analysis indicated that the cinnamon extract acted as the reducing and capping agents on the surface of Ag NPs. RLS technique was used as the detection method. Light-scattering properties of the synthesized nanoparticles in the presence or absence of bisphenol A was selected as the detection signal. Under the optimal conditions, the linear dynamic range and RSD were found to be 0.01–10.0 mg L?1 and 2.78% (n?=?3), respectively. A limit of detection of 0.005 mg L?1 was obtained for the determination of bisphenol A. The obtained results showed successful application of the method for the analysis of bisphenol A in real samples. 相似文献
70.
Simin Nazari Mosadegh Keshavarz Bahador Karami Nasir Iravani Masoumeh Vafaee-Nezhad 《中国化学快报》2014,25(2):317-320
Imidazol-1-yl-acetic acid is introduced as a new, efficient and recyclable green bifunctional organocatalyst for the synthesis of 1,8-dioxooctahydroxanthenes under solvent-free conditions. This catalyst is water soluble and can be separated from the products by simple filtration. The filtrate can be evaporated to dryness and recrystallized from cool methanol to give the recovered catalyst. This organocatalyst was used for the synthesis of 1,8-dioxooctahydroxanthenes under solvent-flee conditions and recycled up to 8 consecutive runs without any losing of its efficiency. 相似文献