Pd-Catalyzed Acyl C–O Bond Activation for Selective Ring-Opening of α-Methylene-β-lactones with Amines
摘要:
A Pd-catalyzed ring-opening of beta-lactones with various types of amines (primary, secondary, and aryl) to provide beta-hydroxy amides with excellent selectivity toward acyl C-O bond cleavage is reported. The utility of this protocol is demonstrated in an asymmetric kinetic resolution providing enantioenriched a-methylene-beta-lactones.
2<i>H</i>-Chromene-3-carboxylic Acid Synthesis via Solvent-Controlled and Rhodium(III)-Catalyzed Redox-Neutral C–H Activation/[3 + 3] Annulation Cascade
作者:Zhi Zhou、Mengyao Bian、Lixin Zhao、Hui Gao、Junjun Huang、Xiawen Liu、Xiyong Yu、Xingwei Li、Wei Yi
DOI:10.1021/acs.orglett.8b01477
日期:2018.7.6
redox-neutral synthesis of 2H-chromene-3-carboxylic acids from N-phenoxyacetamides and methyleneoxetanones has been realized via a solvent-controlled and rhodium(III)-catalyzed C–H activation/unusual [3 + 3] annulation sequence. This transformation represents the first example of using an α-methylene-β-lactone unit as the three-carbon source in transition-metal-catalyzed C–H activationsthroughselective alkyl
Rh(III)‐Catalyzed C−H Activation of 2‐Aryl Quinazolinones and Coupling with 2‐Carboxyl Allylic Alcohols for the Synthesis of β‐Aryl Ketone Substituted Quinazolinones
An efficient strategy for access 2-(2-β-aryl ketone) substituted 2-arylquinazolinones was described. The reaction bewteen 2-aryl quinazolinones and 2-carboxyl allylic alcohols was catalyzed by [RhCp*Cl2]2-CF3COOAg through C−H activation and underwent facile decarboxylation, to give the corresponding 2-(2-β-aryl ketone) substituted phenyl quinazolinones in good to excellent yields with broad substrate
Stereoselective generation and facile dimerization of (E)-2-methylene-3-alkenoic acid esters
作者:Wolfgang Poly、Dietmar Schomburg、H. M. R. Hoffmann
DOI:10.1021/jo00251a009
日期:1988.8
Pd-Catalyzed Acyl C–O Bond Activation for Selective Ring-Opening of α-Methylene-β-lactones with Amines
作者:Christian A. Malapit、Donald R. Caldwell、Nicole Sassu、Samuel Milbin、Amy R. Howell
DOI:10.1021/acs.orglett.7b00494
日期:2017.4.21
A Pd-catalyzed ring-opening of beta-lactones with various types of amines (primary, secondary, and aryl) to provide beta-hydroxy amides with excellent selectivity toward acyl C-O bond cleavage is reported. The utility of this protocol is demonstrated in an asymmetric kinetic resolution providing enantioenriched a-methylene-beta-lactones.
Rh(III)-Catalyzed <i>N</i>-Amino-Directed C–H Coupling with 3-Methyleneoxetan-2-ones for 1,2-Dihydroquinoline-3-carboxylic Acid Synthesis
polarity and revealing expanded reactivity patterns. Through this analysis formalism, polarity matching has been established for Rh(III)-catalyzed N-amino-directed C–H coupling with 3-methyleneoxetan-2-ones, providing efficient access to 1,2-dihydroquinoline-3-carboxylic acids. The identified reaction, by virtue of the internal oxidative mechanism, showcases mild reaction conditions (room temperature),