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61.
The activity of the [Pd{C6H4(CH2N(CH2Ph)2)}(µ-Br)]2 complex was investigated in the synthesis of symmetrical biaryls under both conventional and microwave irradiation conditions, and their results were compared. This complex is efficient, stable, and not sensitive to air or moisture and is a catalyst for the homo-coupling reaction of aryl iodides, bromides, and even chlorides. The products were produced in excellent yields in short reaction times using a catalytic amount of [Pd{C6H4(CH2N(CH2Ph)2)(µ-Br)]2 complex in N-methylpyrolidine (NMP) at 130 °C. In comparison to conventional heating conditions, the reactions under microwave irradiation gave better yields in shorter reaction times. 相似文献
62.
Majid M. Heravi Vahideh Rasmi Fatemeh F. Bamoharram Sodeh Sadjadi Lida Fotouhi Samahe Sadjadi 《合成通讯》2013,43(22):4109-4116
Silica-supported Preyssler nanoparticles appear to be a new and efficient solid acid catalyst for an economical, and environmentally benign one-pot synthesis of 3-substituted phthalides. 相似文献
63.
Majid M. Heravi Hamideh Alinejhad Fatemeh Derikvand Hossein A. Oskooie Bita Baghernejad Fatemeh F. Bamoharram 《合成通讯》2013,43(14):2033-2039
We report here two simple methods for the synthesis of benzo[c]acridine derivatives from three-component, one-pot condensation of 1-naphthylamine, dimedone, and a variety of substituted aldehydes in the presence of a catalytic amount of NH2SO3H or H6P2W18O62 · 18H2O under solvent-free conditions at 120 °C or in refluxing ethanol. 相似文献
64.
A simple, efficient, and rapid method for high-yielding regioselective mono bromination of phenols and anilines has been achieved by treatment with N-bromasaccharin in the presence of a catalytic amount of tungstophosphoric acid. 相似文献
65.
A novel chiral ionic liquid (CIL) based on nicotinium salt has been synthesized and used as an efficient asymmetric chiral catalyst for reduction of acetophenone derivatives with NaBH4 in methanol at room temperature. The optically active alcohols were obtained in low to moderate enantiomeric excess in a short reaction time. 相似文献
66.
Majid M. Heravi Fatemeh Nahavandi Samaheh Sadjadi Hossein A. Oskooie Fatemeh F. Bamoharram 《合成通讯》2013,43(4):498-503
Reaction of aldehydes and 4-hydroxycoumarin in the presence of catalytic amount of silica-supported Preyssler nanoparticles led to synthesis of bis-coumarins in excellent yields. 相似文献
67.
A simple, inexpensive, and efficient new synthesis of 4(3H)-quinazolinones from the reaction of 2-aminobenzamide with aroyl chlorides in the presence of two new halogen-free Brønsted acidic ionic liquids, 3-methyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate [(CH2)4SO3HMIM][HSO4] and 1-(4-sulfonic acid) butylpyridinium hydrogen sulfate [(CH2)4SO3HPY][HSO4], green and reusable catalysts, with excellent product yields under solvent-free conditions is reported. The products could be separated simply from the catalyst, and the catalyst could be recycled without noticeably decreasing the catalytic activity. 相似文献
68.
A new and efficient method to synthesize a 3,3,6,6,9‐aryl‐1,8‐dioxo‐octahydroxanthene derivative using diammonium hydrogen phosphate as catalyst was performed in water at room temperature in a short periods. 相似文献
69.
Farrokh Gharib Ali Shamel Fatemeh Jaberi Ali Farajtabar 《Journal of solution chemistry》2013,42(5):1083-1095
The solvatochromic properties of the free base and the protonated 5,10,15,20-tetrakis(4-trimethyl-ammonio-phenyl)-porphine tetratosylate (TTMAPP) were studied in pure water, methanol, ethanol, 2-propanol, and their corresponding aqueous mixtures. The correlation of the empirical solvent polarity scale (E T) values of TTMAPP with composition of the solvents were analyzed by the solvent exchange model of Bosch and Roses to clarify the preferential solvation of the probe dyes in the binary mixed solvents. The solvation shell composition effects in preferential solvation of the solute dyes were investigated in terms of both solvent–solvent and solute–solvent interactions and also the local mole fraction of each solvent composition was calculated in the cybotactic region of the probe. The effective mole fraction variation may provide significant physicochemical insights in the microscopic and molecular level of interactions between TTMAPP species and the solvent components and, therefore, can be used to interpret the solvent effect on kinetics and thermodynamics of TTMAPP. 相似文献
70.
F. Ditrói F. Tárkányi S. Takács A. Hermanne H. Yamazaki M. Baba A. Mohammadi 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(2):853-865
As a part of our series of studies on charged particle induced reactions on various target materials, proton induced excitation functions on natural cobalt have been determined by using the stacked-foil technique. In these measurements the radionuclides 55,56,57,58Co, 51Cr, 52,54,56Mn and 56,57Ni have been identified. For the above mentioned nuclides the cross-sections were derived from the measured activities and were compared with the literature data and with the results of EMPIRE code calculations and tabulated values in the TENDL 2011 library (based on TALYS code calculations). The agreement with previous measurements and with theoretical values was acceptable. 相似文献