نتایج جستجو برای: methyl acetoacetate
تعداد نتایج: 111325 فیلتر نتایج به سال:
Chemical recovery of methyl acetoacetate from the amoxicillin plant’s waste stream was investigated. In process of amoxicillin production for activation of amoxicillin molecule, hydrolysis takes place at final stage. As a result methyl acetoacetate is formed. Liquid-liquid extraction was employed for the recovery of methyl acetoacetate from the waste stream. Diluted alkaline solution was used a...
3-Methyl-1-phenylpyrazol-5-one and its derivatives prepared using ethyl acetoacetate, phenyl hydrazine and its derivatives. Ethyl acetoacetate reacted with phenylhydrazine at reflux temperature to give 3-methyl-1-phenylpyrazol-5-one crude and recrystlized from diluted ethanol to give pure 3-methyl1-phenylpyrazol-5-one. Different pyrazolone derivatives were prepared by using different phenyl hyd...
Anilines 1a-h on reaction with potassium thiocyanate and bromine in acetic acid yielded substituted 2-amino[2,1-b][1,3]benzothiazoles 3a-h. The compounds 3a-h on reaction with ethyl acetoacetate and pheylidine acetoacetate, yielded, 2-methyl-4-H-pyrimido[2,1b][1,3]benzothiazole-4-ones 4a-h and ethyl 4-phenyl-2-methyl-4H–pyrimido[2,1b][1,3]benzothiazole-3-carboxylates 5a-h respectively. Pheylidi...
an efficient synthesis of polyhydroquinoline derivatives was reported via four-component coupling reactions of aldehydes, 1,3-dicarbonyl ketones (dimedone or 1,3-cyclohexanedione), ethyl acetoacetate or methyl acetoacetate and ammonium acetate in the presence of a catalytic amount of nanocrystalline tio2 under solvent free conditions. the reported method is mild, rapid and has the advantages su...
The observation of a coenayme A (CoA)-catalyzed acetoacetate synthesis from acetate and adenosinetriphosphate in pigeon liver extracts (1) grouped this reaction with the larger family of acetylation reactions. Furthermore it furnished partial confirmation of an earlier calculation (2) showing that 16,000 calories are required for the condensation of two acetates to acetoacetate. Thus, one energ...
The Pechmann reaction of substituted phenols 1a-e with methyl acetoacetate (2) can be activated by boron trifluoride dihydrate (3) to give the corresponding 4-methyl- coumarin derivatives 4a-e in excellent yield (98-99 %).
The mechanism of the TiCl4-promoted condensation of methyl acetoacetate, isobutyraldehyde, and indole was studied by a combination of theoretical and experimental techniques. The energy profile of plausible reaction paths was evaluated by DFT calculations, and various reaction intermediates were isolated or observed in solution by NMR spectroscopy. Theoretical and experimental results indicate ...
Cycloaddition of nitrile imines 4 generated in situ by the catalytic dehydrogenation of diphenyl hydrazones 3 using Chloramine-T (CAT) as oxidant in glacial acetic acid with enolic form of ethyl acetoacetate 5 afforded Ethyl 3-aryl-5-methyl-1-phenyl-1H-pyrazol-4-carboxylate 6 in 80% yield. The said pyrazoles 6 refluxed with 80% hydrazine hydrate using absolute alcohol as solvent for about 2-3 h...
An efficient synthesis of polyhydroquinoline derivatives was reported via four-component coupling reactions of aldehydes, 1,3-dicarbonyl ketones (dimedone or 1,3-cyclohexanedione), ethyl acetoacetate or methyl acetoacetate and ammonium acetate in the presence of a catalytic amount of nanocrystalline TiO2 under solvent free conditions. The reported method is mild, rapid and has the advantages su...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید