115995-19-2Relevant academic research and scientific papers
Method for preparing nitrone from secondary amine
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Paragraph 0019, (2016/11/28)
The invention relates to a method for preparing nitrone from secondary amine. The method comprises the steps of adding 2 mmol of the secondary amine into a reactor, sequentially adding 4-5 mL of water, 0.02-0.03 mmol of tetrabutylammonium bromide, 0.02-0.08 mmol of a catalyst WO3-x and 3-6 mmol of a hydrogen peroxide solution with the concentration being 30-50%, and stirring the mixture for 2-6 hours at the temperature of 25-60 DEG C; or adding 2 mmol of the secondary amine into a reactor, adding 3-5 mL of polar solvent, 0.02-0.08 mmol of a catalyst WO3-x ad 3-6 mmol of a hydrogen peroxide solution with the concentration being 30-50%, and stirring the mixture for 2-6 hours at the temperature of 25-60 DEG C; diluting a mixed solution obtained after a reaction to 15-20 mL, conducting extraction, concentration and column chromatography isolation, and collecting a product. The catalyst adopted in the method is WO3-x nanosheets having oxygen vacancies and is high in catalytic oxidation activity; raw materials of the method are wide in source, the reaction condition is simple, the reaction temperature is low, the nitrone yield is high, and water serves as reaction solvent, so that the whole reaction steps are free of pollution, environmentally friendly and low in cost, high industrial application value is achieved, and in addition, great environmental and social significance is achieved.
Iridium-Catalyzed Direct C-H Sulfamidation of Aryl Nitrones with Sulfonyl Azides at Room Temperature
Pi, Chao,Cui, Xiuling,Wu, Yangjie
, p. 7333 - 7339 (2015/08/18)
Ir(III)-catalyzed direct C-H sulfamidation of aryl nitrones has been developed to synthesize various sulfamidated nitrones in moderate to excellent yields with excellent regioselectivity and broad functional group tolerance. This transformation could proceed smoothly at room temperature with low catalyst loading in the absence of external oxidants, acids, or bases. Molecular nitrogen was released as the sole byproduct, thus providing an environmentally benign sulfamidation process. And this protocol could efficiently apply to synthesize the substituted benzisoxazoline via one-step transformation from the product.
Synthesis and Characterization of Phenyl-Substituted C-Phenyl-N-tert-butylnitrones and Some of Their Radical Adducts
Hinton, Randall D.,Janzen, Edward, G.
, p. 2646 - 2651 (2007/10/02)
Synthesis of C-phenyl-N-tert-butylnitrone (PBN) and several of its analogues with substituents in the 2-, 3-, or 4-position on the phenyl ring is described.While a one-pot reduction/condensation method proved suitable for the most compounds, it was necessary to prepare some examples by direct condensation or through oxidation of the appropriate imine.The 1H NMR data for the 3-X- and 4-X-PBN's can be correlated with the Hammett equation.For the 3-X series Δδ for the α-proton correlates best with ?+ and has a correlation coefficient of 0.90.For the 4-X series a dual substituent parameter equation using ?R0 gives the best correlation with r = 0.99.The hyperfine splitting constants (hfsc's) of HO and HOO adducts of serveral substituted PBN's are also included and their correlation with the Hammett equation is discussed.
