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971.
972.
Fragmentation pathways and structural characterization of organophosphorus compounds related to the Chemical Weapons Convention by electron ionization and electrospray ionization tandem mass spectrometry 下载免费PDF全文
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The one-pot reactions of aryl glyoxals with acetylacetone and urea using molybdate sulfuric acid (5 mol %) lead to the novel functionalized 5-acetyl-4-(aryloyl)-3,4-dihydropyrimidinones, which readily undergo the Knorr condensation with hydrazines to produce new pyrimido[4,5-d]pyridazines. The present strategies are in accordance with green chemistry principles through the use of a safe and recyclable catalyst under solvent-free conditions. 相似文献
975.
Three‐Step Synthesis of Novel 2‐Aryl‐3‐benzamidobenzofurans: Regiospecific Reactions Catalyzed by Molybdate Sulfuric Acid 下载免费PDF全文
Fatemeh Hashemi Bahador Karami Saeed Khodabakhshi 《Journal of heterocyclic chemistry》2014,51(2):322-326
A solvent‐free and synthetic pathway to novel benzofuran derivatives, starting from oxidation of phenyl ketones to arylglyoxals in three steps was developed. The molybdate sulfuric acid catalyzed the reaction of arylglyoxals with benzamide and phenols to afford 2‐aryl‐3‐benzamidobenzofurans in high yield. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, 1H NMR, and 13C NMR spectral data. The present methodology offers several advantages such as non‐hazardous reaction condition, simple operation, and work‐up procedure. 相似文献
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977.
Triphenyl(propyl‐3‐sulfonyl)phosphoniumtrifluoromethanesulfonate {[TPPSP]OTf} as a reusable, green and benign ionic liquid catalyst has been used in the Hantzsch four‐component (synthesis of polyhydroquinolines) and three‐component (synthesis of acridines) condensation reactions of 1,3‐diones, β‐ketoesters, aldehydes, ammonium acetate and aniline derivatives in the presence of 0.5 mol% of {[TPPSP]OTf} at room temperature under solvent‐free conditions. The new ionic liquid catalyst was fully characterized using infrared, 1H NMR, 13C NMR, 31P NMR, 19F NMR and mass spectroscopies, and thermogravimetric and derivative thermogravimetric analyses. Additionally, the recovered catalyst can be recycled at least five times in subsequent reactions without significant loss in catalytic activity. The new synthesis technique presented offers numerous advantages of safety, mild conditions, simplicity, short reaction time, high yields and easy workup compared to the traditional synthesis method. Twenty products have been reported for the first time. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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979.
Baghban Alireza Pourfayaz Fathollah Ahmadi Mohammad Hossein Kasaeian Alibakhsh Pourkiaei Seyed Mohsen Lorenzini Giulio 《Journal of Thermal Analysis and Calorimetry》2018,131(2):1213-1220
Journal of Thermal Analysis and Calorimetry - The effect of Na2CO3 additive on the steam gasification characteristics of Sunjiahao (SJH) coal char was studied in the present paper. Na2CO3-catalyzed... 相似文献
980.
Asen Parvin Shahrokhian Saeed Zad Azam Iraji 《Journal of Solid State Electrochemistry》2018,22(4):983-996
Journal of Solid State Electrochemistry - Polyaniline/graphene oxide (PANI/GO) co-doped with Zn2+ and Fe3+ was synthesized via a simple and low cost one-step chronoamperometry method on stainless... 相似文献