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41.
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
42.
The Reaction Activity of Aromatic Carbonyl Compounds with Diphenylphosphine Oxide Studied by 31P NMR
Jinyun Zheng Xiangming Feng Yujian Yu Xiaomin Zhen Yufen Zhao 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1080-1087
Abstract A series of α-hydroxyphosphine oxides were prepared by the reactions of diphenylphosphine oxide and aromatic carbonyl compounds and characterized by 1H NMR, 13C NMR, 31P NMR, FT-IR, ESI-MS, and HR-MS spectra. The reaction rates and experimental conditions of aromatic aldehydes and aromatic ketones were obviously different due to the activity of their carbonyls. The different substituents of the aromatic aldehydes affected the reaction rate too, and the quantitative reactivity of their substituent conformed to the Hammett equation. The results were confirmed by 31P NMR spectroscopy. 相似文献
43.
Razieh Doostmohammadi Malek Taher Maghsoodlou Nourallah Hazeri Sayyed Mostafa Habibi-Khorassani 《中国化学快报》2013,24(10):901-903
A facile one-pot synthesis of 3,4,5-substituted furan-2(5H)-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using tetra-n-butylammonium bisulfate as a catalyst has been developed. 相似文献
44.
《Green Chemistry Letters and Reviews》2013,6(2):123-125
Abstract A simple, rapid, efficient and environmentally benign procedure for the synthesis of chalcones has been achieved by grinding aryl aldehydes and acetophenones with anhydrous barium hydroxide (C-200) in the absence of any solvent. The use of organic solvent for extraction of compound is also avoided. This present method is highly useful for the synthesis of 2′-hydroxy chalcones, required intermediates for the synthesis of flavanoids. 相似文献
45.
Lipeng Zhou Beibei Dong Si Tang Hong Ma Chen Chen Xiaomei Yang Jie Xu 《Journal of Energy Chemistry》2013,22(4):659-664
Sulfonated carbon as a strong and stable solid acid catalyst exhibited excellent catalytic performance in various acid-catalyzed reactions. Here, sulfonated carbon, as catalyst for oxidation reaction, was prepared via the carbonization of starch followed by sulfonation with concentrated sulfuric acid. N2 physisorption, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray fluorescence and acid-base titration were used to characterize the obtained materials. The catalytic activity of sulfonated carbon was studied in the oxidation of aldehydes to carboxylic acids using 30 wt% H2O2 as oxidant. This oxidation protocol works well for various aldehydes including aromatic and aliphatic aldehydes. The sulfonated carbon can be recycled for three times without obvious loss of activity. 相似文献
46.
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
47.
N‐aroyl‐N′‐arylsulfonylhydrazines can be obtained by oxidation of aromatic aldehyde N‐arylsulfonylhydrazones with bis(trifluoroacetoxy)iodobenzene in acetone at room temperature in mild to good yields. 相似文献
48.
Some dihydrofuro-fused coumarin derivatives were synthesized from 3-aminoalkyl-4-hydroxycoumarin via in situ generation of N-ylide. The 3-aminoalkylated 4-hydroxycoumarin derivatives were synthesized from one-pot, three-component reaction of 4-hydroxycoumarin, aryl aldehydes, and secondary amines in ethanol at room temperature. Again, when salicylaldehyde was employed instead of benzaldehyde, interestingly pyranocoumarins were obtained. The reaction protocol can be further explored toward the synthesis of many other heterocyclic fused dihydrofurans. 相似文献
49.
Aminosulfonic acid is an environmentally friendly catalyst. Grinding a mixture of aromatic aldehydes, barbituric acid, and H2NSO3H at room temperature (without any solvent) gave 5‐arylidene barbituric acid in high yields, providing a simple and efficient route to synthesis of these compounds. 相似文献
50.
1,4-Diazabicyclo[2.2.2]octane (DABCO) has been used as a mild and efficient catalyst for the synthesis of various tetrahydrobenzo[b]pyran derivatives via a one-pot, three component condensation of aromatic aldehydes, dimedone, and active methylene compounds. This method provides several advantages: a simple workup procedure, environmental friendliness, neutral conditions, and good yields. In addition, water or 50% aqueous ethanol was chosen as a green solvent.