The synthesis and some reactions of N-hydroxycarbamates
作者:E. Boyland、R. Nery
DOI:10.1039/j39660000346
日期:——
chloroformate, gave N-hydroxy-N-phenylurethane. Hydroxylamine hydrochloride and ethyl chloroformate yielded a product which changed into hydroxyurethane. Alkyl N-hydroxycarbamates and hydroxyurea gave O-xanthydryl derivatives. The N-hydroxycarbamates with aqueous dipotassium tetracyanonickelate(II) formed dipotassium tricyanonitrosylnickelate(II). No evidence of a Lossen-type rearrangement during the acid
羟胺和氯甲酸烷基酯在碱性介质中反应,以形成ñ - , - NO -二- ,和NNO -三烷氧羰基羟胺,依次。N-甲基羟胺类似地得到N-和NO-二烷氧基羰基-N-甲基-羟胺,O-甲基羟胺产生N-和NN-二烷氧基羰基-O-甲基羟胺。N-苯基羟胺与1当量的氯甲酸乙酯反应,得到N-羟基-N-苯基氨基甲酸酯。盐酸羟胺和氯甲酸乙酯产生产物,其变为羟基氨基甲酸酯。N-羟基氨基甲酸酯烷基和羟基脲得到O-黄羟基衍生物。所述Ñ -hydroxycarbamates用含水四氰二钾(II)而形成二钾tricyanonitrosylnickelate(II)。在这些羟氨基衍生物的酸和碱水解过程中,没有证据表明发生了洛森型重排。讨论了可能的水解机理。
The reaction of hydroxylamine with aspirin
作者:Michelle Medeiros、Bruno S. Souza、Elisa S. Orth、Tiago A.S. Brandão、Willian Rocha、Anthony J. Kirby、Faruk Nome
DOI:10.3998/ark.5550190.0012.738
日期:——
Hydroxylamine reacts with aspirin in aqueous solution at 25 °C predominantly through oxygen, to give O-acetylhydroxylamine as the initial product (Scheme 3). The reaction is much faster than the intramolecular general base catalysed hydrolysis of the carboxylate anion, as it is also for the CO2H form of aspirin. Both reactions are faster than expected, consistent with moderate activation and/or proton
羟胺与阿司匹林在 25 °C 的水溶液中主要通过氧气反应,得到 O-乙酰羟胺作为初始产物(方案 3)。该反应比分子内一般碱催化的羧酸根阴离子水解快得多,对于阿司匹林的 CO2H 形式也是如此。这两种反应都比预期的要快,这与 CO2 - 和 CO2H 基团对羟氨分解的适度活化和/或质子转移催化一致。计算支持氧攻击作为首选反应,但不允许在涉及 NH2OH 和 + NH3–O – 作为有效亲核试剂的机制之间做出明确选择。
13C NMR data for 7- and/or 9-aza-substituted naphthalenecyclolignans
作者:M. Angeles Castro、José M. Miguel del Corral、M. Luisa López-Vázquez、Pablo A. García、Arturo San Feliciano、Marina Gordaliza