Developing the Scope of O→C Aryl Migrations: Exploring Amide Substrates as Potential Precursors for Asymmetric Reactions
作者:Dana Ameen、Timothy J. Snape
DOI:10.1002/ejoc.201301716
日期:2014.3
production of diasteromerically enriched α-aryl carbonyl compounds has been achieved. Although only modest diastereoselectivies are observed, they demonstrate the potential of the method for further optimisation. It also appears that reactions that proceed through a five-membered spirocyclic transition state rearrange, whereas those proceeding through a six-membered transition state do not, but stop at
Synthesis of Unsymmetrical Diaryl Acetamides, Benzofurans, Benzophenones, and Xanthenes by Transition-Metal-Free Oxidative Cross-Coupling of <i>sp</i><sup>3</sup> and <i>sp</i><sup>2</sup> C–H Bonds
A chemo- and regioselective intermolecular sp3 C–H and sp2 C–H coupling reaction for C–C bond formation is described to access unsymmetrical diaryl acetamides under TM-free conditions from sec- and tert-arylacetamides and nitroarenes using tert-butoxide base in DMSO at room temperature. The coupling partners with sensitive functionalities such as chloro, bromo, hydroxy, and cyano were also amenable
C−H hydroxylation of aryl acetamides and alkyl phenylacetyl esters was accomplished via challenging distal weak O‐coordination by versatile ruthenium(II/IV) catalysis. The ruthenium(II)‐catalyzedC−H oxygenation of aryl acetamides proceeded throughC−Hactivation, ruthenium(II/IV) oxidation and reductive elimination, thus providing step‐economical access to valuable phenols. The p‐cymene‐ruthenium(II/IV)