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排序方式: 共有354条查询结果,搜索用时 15 毫秒
91.
Tahereh Sharafi Majid M. Heravi Mitra Ghassemzadeh Bernhard Neumüller 《无机化学与普通化学杂志》2005,631(12):2297-2299
The reaction of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione (AMTT, 1 ) with AgNO3 and triphenylphosphane in a molar ratio 1:1:2 in ethanol led to the dimeric complex {[Ag(AMTT)(PPh3)2]NO3}2·4EtOH ( 2 ). 2 was characterized by elemental analyses, IR, 31P NMR spectroscopy as well as single crystal X‐ray diffraction. Crystal data for 2 at ?80 °C: space group with a = 1265.5(2), b = 1300.9(2), c = 1509.5(2) pm, α = 83.77(2)°, β = 79.22(2)°, γ = 62.89(2)°, Z = 2, R1 = 0.0330. 相似文献
92.
Mohammad Yazdanbakhsh Mohammad Hakimi Majid M. Heravi Roland Boese 《无机化学与普通化学杂志》2006,632(14):2201-2203
The reaction of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione with AgNO3 in methanol led to the complex [Ag(ATT)2]NO3 ( 2 ). 2 was characterized by elemental analyses, IR, 1HNMR and Raman spectroscopy as well as single‐crystal X‐ray diffraction. Crystal data for 2 at ?70 °C: space group P21/n with a = 1356.7(12), b = 770.4(7), c = 1475.2(12) pm, β = 111.730(15)°, Z = 4, R1 = 0.0402. 相似文献
93.
Majid M. Heravi Radineh Motamedi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2329-2334
A series of 2-(2,4-difluorophenyl)-1-(1H-1,2,4 triazol-1-yl-methyl)-3-(substituted heterocycl)-propan-2-ol, which are analogous to fluconazole, were synthesized via the reaction of 2-(2,4-difluorophenyl)-2-[1-(1,2,4-triazolmethide)]oxiran with various heterocyclic systems. 相似文献
94.
The electrochemical oxidation of catechols (1a-c) has been studied in the presence of 6-methyl-1,2,4-triazine-3-thion-5-one 3 in aqueous sodium acetate, using cyclic voltammetry and controlled-potential coulometry. A plausible mechanism for the oxidation of catechols and their reaction with 3 is presented. All the catechol derivatives (1a-c) were converted into 7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives (6a-c) through a Michael-type addition reaction of 3 to anodically generated o-quinones. The electrochemical syntheses of 6a-c were successfully performed in one pot in an undivided cell using an environmentally friendly method with high atomic economy. 相似文献
95.
Hassanzadeh A Zeini-Isfahani A Habibi MH Heravi MR Abdollahi-Alibeik M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,63(2):247-254
Azo-hydrazone tautomeric behavior of polyazo Solophenyl red 3BL (C.I. Direct 80) dye in different solvents (water, methanol and DMSO) was investigated using 1H, 13C, NH, HH, CH COSY, HH NOESY NMR techniques and UV-vis spectroscopy. Two-dimensional NMR experiments were used to assign 1H, 13C and 15N NMR lines unambiguously. Results showed that the hydrazone-form proton NMR signal appeared in the weakest field with respect to tetramethylsilane, in comparison with the amide and phenolic proton NMR signals. UV-vis absorption spectroscopic evidences showed that azo-hydrazone mixture exists in water and DMSO solvents, but in methanol, only azo tautomer was dominant, which was in a good agreement with NMR spectroscopic results. 相似文献
96.
Highly regiospecific mononitration of phenol and substituted phenols was accomplished employing a metal nitrate and a catalytic amount of KHSO4 in acetonitrile. An exclusive ortho‐selectivity was observed with excellent yields. A variety of metal nitrates were used to obtain o‐nitrophenols exclusively in good to excellent yields. The use of KHSO4 is key for the selectivity observed. 相似文献
97.
98.
Abolghasem Davoodnia Majid M. Heravi Leila Rezaei-Daghigh Niloofar Tavakoli-Hoseini 《Monatshefte für Chemie / Chemical Monthly》2009,13(3):1499-1502
Abstract
Efficient and convenient synthesis of β-acetamido ketones has been achieved by one-pot reaction of acetophenone, aryl aldehydes, acetyl chloride, and acetonitrile in the presence of 3-methyl-1-(4-sulfonylbutyl)imidazolium hydrogensulfate [HO3S(CH2)4MIM][HSO4], a Br?nsted-acidic ionic liquid, as a green and reusable catalyst in solvent-free media at room temperature. The catalyst could be recycled and reused without noticeable decrease in catalytic activity. 相似文献99.
Methanesulfonic acid efficiently catalyzes the one‐pot, three component reaction of an aromatic aldehyde, malonitrile and α or β‐naphthol to yield 2‐amino‐4H‐chromenes in very good yields. 相似文献
100.
Majid M. Heravi Yahya S. Beheshtiha Mitra Ghasemzadeh Rahim Hekmatshoar Nooshin Sarmad 《Monatshefte für Chemie / Chemical Monthly》2000,131(2):187-190
Summary. Ammonium chlorochromate adsorbed on montmorillonite K-10 rapidly regenerates carbonyl compounds from their corresponding
oximes under microwave irradiation and solvent-free conditions.
Received October 11, 1999. Accepted (revised) November 15, 1999 相似文献