Rh(III)-Catalyzed Directed C−H Olefination Using an Oxidizing Directing Group: Mild, Efficient, and Versatile
摘要:
An efficient Rh(III)-catalyzed oxidative olefination by directed C-H bond activation of N-methoxybenzamides is reported. In this mild, practical, selective, and high-yielding process, the N-O bond acts as an internal oxidant. In addition, simply changing the substituent of the directing/oxidizing group results in the selective formation of valuable tetrahydroisoquinolinone products.
Divergent Synthesis of Tunable Cyclopentadienyl Ligands and Their Application in Rh-Catalyzed Enantioselective Synthesis of Isoindolinone
作者:Wen-Jun Cui、Zhi-Jie Wu、Qing Gu、Shu-Li You
DOI:10.1021/jacs.0c02813
日期:2020.4.22
unprecedented enantioselective [4+1] annulation reaction of benzamides and alkenes was achieved with a broad substrate scope under mild reaction conditions, providing a variety of isoindolinones with excellent regio- and enantioselectivity (up to 94% yield, 97:3 er). Preliminary mechanistic studies suggest that the reaction involves an oxidative Heck reaction and an intramolecular enantioselective alkene
precursors in reactions with thioethers under the catalysis of a commercially available Ru(II) complex, from which a variety of sulfimides were synthesized efficiently and mildly. If an allyl group is contained in the thioether precursor, the [2,3]-sigmatropic rearrangement of the sulfimide occurs simultaneously and the N-allyl-N-(thio)amides were obtained as the final products. Preliminary mechanistic studies
Rh(III)- and Zn(II)-Catalyzed Synthesis of Quinazoline <i>N</i>-Oxides via C–H Amidation–Cyclization of Oximes
作者:Qiang Wang、Fen Wang、Xifa Yang、Xukai Zhou、Xingwei Li
DOI:10.1021/acs.orglett.6b03155
日期:2016.12.2
Quinazoline N-oxides have been prepared from simple ketoximes and 1,4,2-dioxazol-5-ones via Rh(III)-catalyzed C–H activation–amidation of the ketoximes and subsequent Zn(II)-catalyzed cyclization. The substrate scope and functional group compatibility were examined. The reaction features relay catalysis by Rh(III) and Zn(II).
Development of a Traceless Directing Group: Cp*-Free Cobalt-Catalyzed C–H Activation/Annulations to Access Isoquinolinones
作者:Minghui Liu、Jun-Long Niu、Dandan Yang、Mao-Ping Song
DOI:10.1021/acs.joc.9b03073
日期:2020.3.20
A new tracelessdirectinggroup, 2-(hydroxymethyl)pyridine, has been reported for the Cp*-free cobalt-catalyzedC-H activation/annulation reaction to synthesize isoquinolinones. The reaction exhibits good functional group tolerance, affording products in good to excellent isolated yields under mild conditions. Notably, the directinggroup can be removed directly in situ along the catalytic process
The Lossenrearrangement is a classic process for transforming activated hydroxamic acids into isocyanate under basic or thermal conditions. In the current report we disclosed a consecutive Lossenrearrangement/transamidation reaction in which unactivated hydroxamic acids were converted into N-substituted formamides in a one-pot manner under catalyst- and additive-free conditions. One feature of this