- Acid hydrolysis of amides obtained by Beckmann rearrangement of methyl ketones oximes of unsaturated γ-lactone, aromatic, and alicyclic series
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Beckmann rearrangement was performed of oximes of substituted 3-acetyl-4-methyl-5,5-dimethyl(pentamethylene)-2-oxo-2,5-dihydrofuranes in the presence of boron trifluoride etherate. Aiming at establishing the spatial arrangement of the oximes the hydrolysis was carried out of acid amides obtained by Beckmann rearrangement of oximes of methyl ketones belonging to unsaturated γ-lactone series and also to aromatic and alicyclic series. The hydrolysis with 20% sulfuric acid led to the formation of the corresponding acid and amine, and the hydrolysis with acetic and hydrochloric acids resulted in retrobeckmann rearrangement giving the initial oximes.
- Tokmadzhyan
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- Trifluoroacetic Acid Hydroxylamine System as Organocatalyst Reagent in a One-Pot Salt Free Process for the Synthesis of Caprolactam and Amides of Industrial Interest
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In this work we studied the reactivity of the Trifluoroacetic acid hydroxylamine system in the one step salt free synthesis of amides from ketones. A particular regards was paid to the caprolactam synthesis because of its industrial relevance. Synthesis, reactivity and characterization of the hydroxylamine trifluoroacetate is given. Fast oximation reaction of several ketones was gained at room temperature (1?h of reaction quantitative conversion for several ketones). In the same reactor, by raising the temperature at 383?K, the Beckmann rearrangement of the so obtained oximes is easily accomplished in the presence of three equivalent of TFA. The possibility of obtaining the trifluoroacetate of the hydroxylamine with a modified nitric acid hydrogenation reactions was verified, too. Reuse of solvent and trifluoroacetic acid is easily achieved by distillation. Graphical abstract: Salt free one-pot caprolactam and amides process catalyzed by CF3COOH, in the presence of NH2OH TFA as the oximation agent.[Figure not available: see fulltext.].
- Manente,Pietrobon,Ronchin,Vavasori
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p. 3543 - 3549
(2021/03/30)
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- Preparation method of N-methyl-4-hydroxybenzamide
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The invention relates to a preparation method of N-methyl-4-hydroxybenzamide, wherein the preparation method comprises the following steps: 1) adding 4-hydroxybenzoyl chloride and triethylamine into a container, heating under stirring to make the system temperature be 20-50 DEG C, then dropping absolute ethyl alcohol with the dropping time of 0.5-1 h, after the dropping is finished, carrying out a heat preservation reaction for 2-5 h at the temperature of 20-50 DEG C, then carrying out suction filtration of the reaction liquid to remove triethylamine hydrochloride, and thus obtaining a filtrate, namely ethyl 4-hydroxybenzoate; and 2) adding ethyl 4-hydroxybenzoate into the container, stirring and heating to 30-60 DEG C, dropping methylamine with the dropping time of 0.5-1 h, after the dropping is finished, carrying out a heat preservation reaction for 3-5 h at the temperature of 30-60 DEG C, cooling to room temperature, precipitating out a large number of solids, and carrying out suction filtration, to obtain a filter cake, namely N-methyl-4-hydroxybenzamide. Compared with the prior art, with adopting of the stepwise reaction, the yield of N-methyl-4-hydroxybenzamide is greatly improved.
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Paragraph 0022; 0025; 0028; 0031; 0034; 0037; 0039
(2017/07/01)
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- Zirconyl chloride: An efficient, water-tolerant, and reusable catalyst for the synthesis of N-methylamides
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ZrOCl28H2O is a highly effective, water-tolerant, and reusable catalyst for the direct condensation of carboxylic acids and N,N-dimethylurea under microwave irradiation to give the corresponding N-methylamides in moderate to excellent yields. Notably, ZrOCl 28H2O is a potentially useful green catalyst due to its low toxicity, easy availability, low cost, ease of handling, easy recovery, good activity, and reusability. Georg Thieme Verlag Stuttgart ? New York.
- Talukdar, Dhrubajyoti,Saikia, Lakhinath,Thakur, Ashim Jyoti
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experimental part
p. 1597 - 1601
(2011/08/06)
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- On the intractability of estrogen-related receptor α as a target for activation by small molecules
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The estrogen-related receptor α (ERRα) is a potential target for activation in the treatment of metabolic disease. To date, no small-molecule agonists of ERRα have been identified despite several high-throughput screening campaigns. We describe the synthesis and profiling of a small array of compounds designed on the basis of a previously reported agonist-bound crystal structure of the closely related receptor ERRγ. The results suggest that ERRα may be intractable as a direct target for pharmacologic activation.
- Hyatt, Stephen M.,Lockamy, Elizabeth L.,Stein, Rebecca A.,McDonnell, Donald P.,Miller, Aaron B.,Orband-Miller, Lisa A.,Willson, Timothy M.,Zuercher, William J.
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p. 6722 - 6724
(2008/09/17)
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- 11-BETA-HYDROXYSTEROID DEHYDROGENASE 1 INHIBITORS USEFUL FOR THE TREATMENT OF DIABETES, OBESITY AND DYSLIPIDEMIA
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Compounds having Formula (I), including pharmaceutically acceptable salts, hydrates and solvates thereof, are selective inhibitors of the 11β-HSD1 enzyme. The compounds are useful for the treatment of diabetes, such as noninsulin-dependent diabetes (NIDDM), hyperglycemia, obesity, insulin resistance, dylsipidemia, hyperlipidemia, hypertension, Syndrome X, and other symptoms associated with NIDDM.
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- Alpha- haloenamine reagents
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The present invention describes immobilized haloenamine reagents, immobilized tertiary amides, methods for their preparation, and methods of use.
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