1236291-45-4Relevant articles and documents
O - substituted hydroxylamine hydrochloride and its preparation method (by machine translation)
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Paragraph 0093-0095, (2018/10/11)
The present invention provides a O - substituted hydroxylamine hydrochloride and its preparation, wherein the preparation method comprises the following steps: step S1, to the acetyl hydroximic acid ethyl ester in ethanol solution of adding sodium hydroxide, in addition at the same time instillment halohydrocarbon, chloride or acyl chloride substitution reaction to take place, then added to the water in order to separate out the O - substituted [...]; step S2, the said O - substituted [...] adding hydrochloric acid solution in order to produce reflux reaction O - substituted hydroxylamine hydrochloride. According to the embodiment of the invention of the O - substituted hydroxylamine hydrochloride of the preparation method, high purity of the product can be obtained, and the method is safe, easy to process, the process is simple, and is suitable for industrial production. (by machine translation)
Synthesis of α,β-Unsaturated N-Aryl Ketonitrones from Oximes and Diaryliodonium Salts: Observation of a Metal-Free N-Arylation Process
Ma, Xiao-Pan,Shi, Wei-Min,Mo, Xue-Ling,Li, Xiao-Hua,Li, Liang-Gui,Pan, Cheng-Xue,Chen, Bo,Su, Gui-Fa,Mo, Dong-Liang
, p. 10098 - 10107 (2015/11/03)
An efficient transition-metal-free method for the preparation of α,β-unsaturated N-aryl ketonitrones under mild conditions has been developed. This reaction shows good functional group tolerance for both electron-rich and electron-deficient substituents on both oximes and diaryliodonium salts. Two examples of gram-scale preparations have been realized in good yields. Further transformations of these nitrones to different N-heterocycles have been demonstrated. DFT calculations suggest that N-arylation products are formed by [1,3]-phenyl migration of an O-coordinated oximate complex via a four-centered transition state, while the O-arylation products are formed by [1,3]-phenyl migration of a N-coordinated oximate complex.
Metal-free one-pot synthesis of benzofurans
Ghosh, Raju,Stridfeldt, Elin,Olofsson, Berit
supporting information, p. 8888 - 8892 (2014/07/22)
Ethyl acetohydroxamate was efficiently arylated with diaryliodonium salts at room temperature under transition-metal-free conditions. The obtained O-arylated products were reacted in situ with ketones under acidic conditions to yield substituted benzo[b]furans through oxime formation, [3,3]-rearrangement, and cyclization in a fast and operationally simple one-pot fashion without using excess reagents. Alternatively, the O-arylated products could be isolated or transformed in situ to aryloxyamines or O-arylaldoximes. The methodology was applied to the synthesis of Stemofuran A and the formal syntheses of Coumestan, Eupomatenoid 6, and (+)-machaeriol B. Just add salt! A metal-free, room temperature arylation of ethyl acetohydroxamate, followed by an in situ reaction with ketones under acidic conditions yielded substituted benzo[b]furans in a fast and operationally simple one-pot fashion without using excess reagents (see scheme). Alternatively, the O-arylated products could be isolated, hydrolyzed in situ to aryloxyamines, or transformed to O-arylaldoximes. The efficiency of the methodology was demonstrated by the formal synthesis of several biologically active benzofurans.
Pd-catalyzed O-arylation of ethyl acetohydroximate: Synthesis of O-arylhydroxylamines and substituted benzofurans
Maimone, Thomas J.,Buchwald, Stephen L.
supporting information; experimental part, p. 9990 - 9991 (2010/10/04)
An efficient Pd catalyst for the O-arylation of ethyl acetohydroximate with aryl chlorides, bromides, and iodides has been developed. Ethyl acetohydroximate serves as an efficient hydroxylamine equivalent for C-O cross-coupling, thereby allowing for the p
