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以金属硫酸氢盐M(HSO4)n(Ca(HSO4)2,Zn(HSO4)2和过硫酸氢钾制剂oxone○R)为催化剂催化醛、1,3-二羰基化合物和尿素进行缩合反应,在90℃及无溶剂的条件下高收率、一锅法合成了3,4-二氢嘧啶-2(1H)-酮.  相似文献   
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Silica-bonded N-propyl diethylenetriamine sulfamic acid (SBPDSA) is employed as a recyclable catalyst to synthesize α-aminonitriles. These syntheses involved one-pot condensation of an aldehyde, an amine, and trimethylsilyl cyanide under mild reaction conditions at room temperature. SBPDSA was recycled seven times in the condensation of benzaldehyde, aniline, and trimethylsilyl cyanide without reduction of its catalytic activity.  相似文献   
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An efficient heterogeneous Pd catalytic system has been developed, based on immobilization of Pd nanoparticles (PNPs) on a silica-bonded N-propylpiperazine (SBNPP) substrate. The SBNPP substrate effectively stabilizes the PNPs and improves their stability against aggregation. The catalytic activity of this catalyst was investigated in the cyanation of aryl halides with K4[Fe(CN)6 ] as the cyanide source. The catalyst could be recycled several times without appreciable loss of catalytic activity.  相似文献   
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GHAEDI  Mehrorang  TAVALLALI  Hossein  KESHAVARZ  M.  NIKNAM  K. 《中国化学》2009,27(10):2066-2072
A sensitive and simple method for the simultaneous preconcentration of trace amount Cu2+ and Zn2+ ions in some real samples has been established, which is based on the sorption of Cu2+ and Zn2+ on 3‐((1H‐indol‐3‐yl)‐3,4,5‐trimethyl)‐1H‐indole (ITMI) loaded on sodium dodecyl sulfate (SDS) coated alumina. The metal absorbed on the complexes was eluted using 3 mol/L nitric acid. The influences of the analytical parameters including pH and sample volume were investigated. The effects of matrix ions on the retentions of the analytes were also examined. The recoveries of analytes were generally higher than 95% with a low RSD. The method has been successfully applied to content evaluation of these metals in real samples.  相似文献   
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A simple and efficient procedure for the preparation of silica-bound N-propyl triethylenetetramine sulfamic acid(SBPTETSA) by the reaction of silica-bound N-propyl triethylenetetramine(SBPTET) with chlorosulfonic acid in chloroform is described.Silica-bound N-propyl triethylenetetramine sulfamic acid was employed as a recyclable catalyst for the synthesis of 2-amino-4,6-diarylnicotinonitriles from the multi-component reaction of an acetophenone derivative,an aromatic aldehyde,malononitrile,and ammonium acetate under solvent-free conditions at 100 °C.The heterogeneous catalyst was recycled for five consecutive runs in the optimized multi-component reaction of 4-chloroacetophenone,4-chloroenzaldehyde,malononitrile,and ammonium acetate without significant loses to its catalytic activity.  相似文献   
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1-Butyl-3-methylimidazolium hydrogen sulfate [bmim]HSO4 as an acidic ionic liquid was prepared and used as a catalyst for the formylation of alcohols with ethyl formate at room temperature with good to excellent yields. A good selectivity was observed for the formylation of primary alcohols in the presence of tertiary alcohols.  相似文献   
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The protection and deprotection of functionalgroups are indispensable in the synthesis of polyfunc-tional compounds.In addition,several chemical con-versions and multiple sequence syntheses are often re-quired for the protection of hydroxyl groups.Thesily…  相似文献   
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