406-00-8Relevant articles and documents
Electrochemically Tuned Oxidative [4+2] Annulation and Dioxygenation of Olefins with Hydroxamic Acids
Wei, Bang-Yi,Xie, Dong-Tai,Lai, Sheng-Qiang,Jiang, Yu,Fu, Hong,Wei, Dian,Han, Bing
supporting information, p. 3182 - 3188 (2020/12/11)
This work represents the first [4+2] annulation of hydroxamic acids with olefins for the synthesis of benzo[c][1,2]oxazines scaffold via anode-selective electrochemical oxidation. This protocol features mild conditions, is oxidant free, shows high regioselectivity and stereoselectivity, broad substrate scope of both alkenes and hydroxamic acids, and is compatible with terpenes, peptides, and steroids. Significantly, the dioxygenation of olefins employing hydroxamic acid is also successfully achieved by switching the anode material under the same reaction conditions. The study not only reveals a new reactivity of hydroxamic acids and its first application in electrosynthesis but also provides a successful example of anode material-tuned product selectivity.
A Modified System for the Synthesis of Enantioenriched N-Arylamines through Copper-Catalyzed Hydroamination
Ichikawa, Saki,Zhu, Shaolin,Buchwald, Stephen L.
supporting information, p. 8714 - 8718 (2018/07/14)
Despite significant recent progress in copper-catalyzed enantioselective hydroamination chemistry, the synthesis of chiral N-arylamines, which are frequently found in natural products and pharmaceuticals, has not been realized. Initial experiments with N-arylhydroxylamine ester electrophiles were unsuccessful and, instead, their reduction in the presence of copper hydride (CuH) catalysts was observed. Herein, we report key modifications to our previously reported hydroamination methods that lead to broadly applicable conditions for the enantioselective net addition of secondary anilines across the double bond of styrenes, 1,1-disubstituted olefins, and terminal alkenes. NMR studies suggest that suppression of the undesired reduction pathway is the basis for the dramatic improvements in yield under the reported method.
Visible-Light, Photoredox-Mediated Oxidative Tandem Nitroso-Diels–Alder Reaction of Arylhydroxylamines with Conjugated Dienes
Santacroce, Veronica,Duboc, Raphael,Malacria, Max,Maestri, Giovanni,Masson, Geraldine
supporting information, p. 2095 - 2098 (2017/04/24)
Arylhydroxylamines were used in the nitroso-Diels–Alder reaction to generate in situ nitrosoarenes under visible-light, catalytic and aerobic conditions. Mixing a solution of aryl- or heteroarylhydroxylamines with conjuguated dienes in the presence of a catalytic amount of Ru(bpy)3Cl2 afforded 3,6-dihydro-1,2-oxazines in good yields under an oxygen atmosphere.