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排序方式: 共有178条查询结果,搜索用时 15 毫秒
171.
S. Abdolmanaf TaghaviMajid Moghadam Iraj Mohammadpoor-Baltork Shahram TangestaninejadValiollah Mirkhani Ahmad Reza KhosropourVenus Ahmadi 《Polyhedron》2011,30(13):2244-2252
In this work, the catalytic activity of high-valent tetraphenylporphyrinatovanadium(IV) trifluoromethanesulfonate, [VIV(TPP)(OTf)2], in the nucleophilic ring-opening of epoxides is reported. This new V(IV) catalyst was used as an efficient catalyst for alcoholysis with primary (methanol, ethanol and n-propanol), secondary (iso-propanol) and tertiary alcohols (tert-butanol), hydrolysis and acetolysis of epoxides with acetic acid and also for the conversion of epoxides to 1,2-diacetates with acetic anhydride, conversion of epoxides to thiiranes with ammonium thiocyanate and thiourea, and for conversion of epoxides to acetonides with acetone. The catalyst was reused several times without loss of its activity. 相似文献
172.
Iraj Mohammadpoor-Baltork Majid Moghadam Valiollah Mirkhani Shahram Tangestaninejad Hamid Reza Tavakoli 《中国化学快报》2011,22(1):9-12
An efficient,convenient and green method has been introduced for the preparation of 14-aryl(alkyl)-14H-dibenzo[a,j]xanthene and 1,8-dioxooctahydroxanthene derivatives by the reaction of aldehydes with 2-naphthol and 5,5-dimethyl-1,3-cyclohexanedione, respectively,in the presence of ZrO(OTf)2 as a reusable catalyst under solvent-free conditions.In addition,very short reaction times, excellent yields,straightforward procedure,and relatively non-toxicity of the catalyst are other noteworthy advantages of the present method. 相似文献
173.
Mehdi Nooraeipour Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor-Baltork S. Masoud Nabavizadeh 《Transition Metal Chemistry》2011,36(8):861-866
The preparation, characterization, and catalytic activity of W(CO)6 supported on multi-wall carbon nanotubes modified with 4-aminopyridine is reported. The catalyst, [W(CO)5@Apy-MWCNT], was characterized by physico-chemical and spectroscopic methods and found to be an efficient heterogeneous catalyst
for green epoxidation of alkenes with hydrogen peroxide in MeCN solvent. The catalyst showed good stability and reusability
properties in the epoxidation reactions. 相似文献
174.
Iraj Mohammadpoor‐Baltork Ahmad Reza Khosropour Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Mohammad Soltani Arsalan Mirjafari 《Journal of heterocyclic chemistry》2011,48(6):1419-1427
An efficient method for the synthesis of a series of 2,3‐disubstituted‐2,3‐dihydroquinazolin‐4(1H)‐ones is described via one‐pot condensation reaction of isatoic anhydride, aryl aldehydes, and primary amines using a Brønsted acidic ionic liquid, [Hmim][NO3], as a catalyst and medium. The present protocol enjoys convenient reaction and simple work‐up, greenness, short reaction times, and reusable catalyst as well as mild reaction conditions. J. Heterocyclic Chem., (2011). 相似文献
175.
Somayeh Dianat Shahram Tangestaninejad Valiollah Mirkhani Majid Moghadam Iraj Mohammadpoor-Baltork 《Journal of the Iranian Chemical Society》2013,10(3):535-544
In this study, photocatalytic activity of InVO4 and InVO4–TiO2 nanoparticles in the degradation of aqueous solutions of industrial textile azo dyes such as Solophenyl Red 3BL, Coperoxon Nevy Blue RL and Black Nilusun 2BC (abbreviated as SR 3BL, CNB RL and BN 2BC, respectively) and also formaldehyde (abbreviated as FAD) under visible light and ultrasonic irradiations has been compared. The effect of various parameters such as pH, temperature, irradiation time, amounts of nanophotocatalyst and nanocomposite, and ultrasonic intensity on degradation rates was investigated. Then based on the Langmuir–Hinshelwood approach, reaction rates and adsorption equilibrium constants were calculated. The nanophotocatalyst and nanocomposite were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM) and UV‐Vis spectroscopic methods. It was observed that InVO4–TiO2 nanopowder was more reactive than pure InVO4 in the degradation of azo dyes under both conditions of visible light and ultrasonic irradiations. It was noticeable that degradation percent was more under ultrasonic irradiation rather than under visible light irradiation. 相似文献
176.
Maryam Zakeri Majid Moghadam Iraj Mohammadpoor-Baltork Shahram Tangestaninejad Valiollah Mirkhani Ahmad Reza Khosropour Mohammad Alizadeh 《Transition Metal Chemistry》2012,37(1):45-53
The biomimetic epoxidation of alkenes catalyzed by tetraphenylporphyrinatomanganese(III) chloride, [Mn(TPP)Cl], immobilized
on multiwall carbon nanotubes modified with 4-aminopyridine and 4-aminophenol is reported. These heterogenized catalysts were
used as efficient and reusable catalysts for epoxidation of a variety of cyclic and linear alkenes with sodium periodate under
mild conditions. The catalysts, [Mn(TPP)Cl@amine-MWCNT], were characterized by physico-chemical and spectroscopic methods.
The effect of ultrasonic irradiation on these catalytic systems was also investigated. The catalysts were reused several times
without loss of their activity. 相似文献
177.
178.