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101.
Efficient method for direct preparation of 14‐aryl‐14‐H‐dibenzo[a,j]xanthenes through condensation of β‐naphthol with various aromatic aldehydes in the presence of the catalytic amount of [H—NMP]+[HSO4]? under microwave irradiation was described. This method has the advantages such as; very easy reaction workup, absolute separation of catalyst from the reaction mixture and smooth recyclability of catalyst. In this reaction 14‐aryl‐14‐H‐dibenzo[a,j]xanthenes were obtained as desired products in excellent yields and short reaction times via green and one‐pot procedure.  相似文献   
102.
Heterogeneous catalysts were developed by supporting palladium nanoparticles on modified cross‐linked polyacrylamide and successfully applied in Suzuki‐Miyaura cross‐coupling reactions. These catalysts are stable to air and moisture, and no sign of metal leaching was detected during the reactions as judged by elemental analysis of palladium by ICP‐OES technique and hot filtration test, which demonstrates the heterogeneous character of the catalysts. High yields of desired products were resulted by using these phosphine‐free catalysts at temperatures below 80 °C without aid of any additional ligands. The heat stability of the catalysts at the operating temperature was confirmed by thermogravimetric analysis (TGA). These catalysts are easy to use and cost effective. They can be recovered from reaction mixture by a simple filtration and reused in more successive reactions without significant loss in activity. The catalyst activity was restored by an ultrasonication program after deactivation in 10 cycles.  相似文献   
103.
CuO‐CeO2 nanocomposite is reported as a highly efficient and recyclable catalyst for the green synthesis of 1,8‐dioxooctahydroxanthenes in water. This catalyst can be recovered by simple filtration and recycled up to 8 consecutive runs without any losing of its efficiency.  相似文献   
104.
The capability of the B20O30 nanocapsule to store H2, N2, CO, CO2, NH3, CH4, and Cl2 molecules on the outer surface and inside of the cage was investigated using Monte Carlo simulations, long‐range and dispersion corrected density functional theory, and Møller–Plesset second‐order perturbation theory. Also, Monte Carlo simulations were employed to investigate the adsorption behavior of larger number of guest molecules inserted into and onto the larger B80O120 and B20O30@B80O120 cages. Absolute localized molecular orbitals energy decomposition analysis was used to describe the nature of intermolecular interactions in these endohedral and exohedral complexes. It is found that the hydrogen and ammonia gases are diffused to the inside of spherical B20O30 capsule, while other guest molecules prefer to interact with the outer surface of spherical and pyramidal capsules. For B80O120, up to 26 H2 and 11–14 N2, CO, CO2, NH3, and CH4 molecules are stored inside the capsule. The residual molecules are adsorbed on the outer surface of nanocapsule. © 2013 Wiley Periodicals, Inc.  相似文献   
105.
106.
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   
107.
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   
108.
1,1‐Diacetates have been synthesized by the reaction of a variety of aldehydes with acetic anhydride in the presence of cupric nitrate as catalyst under solvent‐free conditions. Ketones were not converted to the corresponding diacetates under these conditions.  相似文献   
109.
The sodium salts of the conjugated bases of uracils undergo highly chemoselective O4-monoalkylation when treated with various alkyl halides in dry DMF, while the use of methyl iodide results in N1+N3-dimethylation. Theoretical evaluations of the chemo- and regioselectivity along with X-ray crystallographic data are presented.  相似文献   
110.
Erbium-165 with 10.3 h physical half-life decays completely by electron capture to the ground state of stable isotope 165Ho and it is an ideal radio lanthanide for Auger electron therapy. Excitation function of 165Er via natEr(p,x)165Tm → 165Er, 166Er(p,2n)165Tm → 165Er, 165Ho(p,n)165Er and 165Ho(d,2n)165Er reactions were calculated using ALICE/ASH (Hybrid and GDH models) and EMPIRE 3.1 codes and then were compared with the reported measurement by experimental data and TENDL-2011. Physical yield and target thickness were evaluated with attention to excitation function, stopping power and SRIM code. 165Er was produced using the sedimentation technique through the natEr (p,x)165Tm → 165Er reaction. The deposited target was irradiated with 15 MeV proton beams at 20 μA current for 1 h. The 165Tm production yield was 26 MBq/μA h at the end of bombardment.  相似文献   
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