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
Product Control using Substrate Design: Ruthenium-Catalysed Oxidative C−H Olefinations of Cyclic Weinreb Amides
作者:Riki Das、Manmohan Kapur
DOI:10.1002/chem.201603126
日期:2016.11.14
A new class of Weinreb amides has been developed as directing groups for the ruthenium‐catalysed regioselective oxidative C−H olefination. The new Weinreb amides successfully inhibit the N−O bond reductive cleavage usually associated with the cationic ruthenium system, thereby keeping intact the synthetic utility of Weinreb amides. Mechanistic studies reveal interesting aspects of the directing group
Dioxazolones as masked ester surrogates in the Pd(<scp>ii</scp>)-catalyzed direct C–H arylation of 6,5-fused heterocycles
作者:Paridhi Saxena、Neha Maida、Manmohan Kapur
DOI:10.1039/c9cc05563k
日期:——
simple and effective Pd(II)-catalyzed regioselectiveC(2)–H arylation of 6,5-fused heterocycles with dioxazolones as a masked ester surrogate undermildconditions is reported. The significance of the arylation is highlighted by the new reactivity demonstrated in dioxazolones via proximal C–H activation of the cyclic carbonate of the hydroxamic acid functionalityunder protic conditions.
A cobalt(III)-catalyzed C-8 selective C–H amidation of quinoline N-oxide using dioxazolone as an amidating reagentundermildconditions is disclosed. The reaction proceeds efficiently with excellent functional group compatibility. The utility of the current method is demonstrated by gram scale synthesis of C-8 amide quinoline N-oxide and by converting this amidated product into functionalized quinolines
Efficient Copper-Catalyzed Multicomponent Synthesis of <i>N-</i>Acyl Amidines via Acyl Nitrenes
作者:Kaj M. van Vliet、Lara H. Polak、Maxime A. Siegler、Jarl Ivar van der Vlugt、Célia Fonseca Guerra、Bas de Bruin
DOI:10.1021/jacs.9b07140
日期:2019.9.25
Direct synthetic routes to amidines are desired, as they are widely present in many biologically active compounds and organometallic complexes. N-Acyl amidines in particular can be used as a starting material for the synthesis of heterocycles and have several other applications. Here, we describe a fast and practical copper-catalyzed three-component reaction of aryl acetylenes, amines, and easily accessible