Visible-Light-Mediated Generation of Nitrogen-Centered Radicals: Metal-Free Hydroimination and Iminohydroxylation Cyclization Reactions
作者:Jacob Davies、Samuel G. Booth、Stephanie Essafi、Robert A. W. Dryfe、Daniele Leonori
DOI:10.1002/anie.201507641
日期:2015.11.16
formation and use of iminyl radicals in novel and divergent hydroimination and iminohydroxylationcyclizationreactions has been accomplished through the design of a new class of reactive O‐aryl oximes. Owing to their low reduction potentials, the inexpensive organic dye eosin Y could be used as the photocatalyst of the organocatalytic hydroiminationreaction. Furthermore, reaction conditions for a unique
Pd-Catalyzed O-Arylation of Ethyl Acetohydroximate: Synthesis of <i>O</i>-Arylhydroxylamines and Substituted Benzofurans
作者:Thomas J. Maimone、Stephen L. Buchwald
DOI:10.1021/ja1044874
日期:2010.7.28
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 preparation of O-arylhydroxylamines from simple aryl halides. Short reaction times and broad substrate scope, including heteroaryl coupling partners, allow access to O-arylhydroxylamines that would be difficult to prepare in a single step by traditional methods. Moreover, the O-arylated products so formed can be directly transformed into substituted benzofurans in a single operation.