A switchable synthesis of N-substituted indole derivatives from phenidones via rhodium-catalyzed redox-neutral C–H activation has been achieved. In this protocol, we firstly disclosed that the reactivity of Rh(III) catalysis could be enhanced through employing palladium acetate as an additive. Some representative features include external oxidant-free, applicable to terminal alkynes, short reaction
Rhodium(III)-Catalyzed [4+3] Annulation of <i>N</i>-Aryl-pyrazolidinones and Propargylic Acetates: Access to Benzo[<i>c</i>][1,2]diazepines
作者:Tingfang Li、Zi Yang、Zhenyu Song、Remi Chauvin、Xiuling Cui
DOI:10.1021/acs.orglett.0c01139
日期:2020.6.5
The generation of 2,3-dihydro-benzo[c][1,2]diazepine derivatives via rhodium(III)-catalyzed [4+3] annulation of pyrazolidinones and propargylic acetates is disclosed. The reaction proceeds smoothly under relatively mild conditions from propargylic acetates as novel C3 synthons. A range of dinitrogen-fused heterocyclic compounds are readily accessed by this approach.
公开了通过铑(III)催化的吡唑烷酮和乙酸炔丙基酯的[4 + 3]环化反应生成2,3-二氢-苯并[ c ] [1,2]二氮杂卓衍生物。在相对温和的条件下,由炔丙基乙酸酯作为新型C 3合成子,可使反应平稳进行。通过该方法可以容易地获得许多二氮稠合的杂环化合物。
Rhodium-Catalyzed [4 + 1] Cyclization via C–H Activation for the Synthesis of Divergent Heterocycles Bearing a Quaternary Carbon
作者:Xiaowei Wu、Haitao Ji
DOI:10.1021/acs.joc.8b00397
日期:2018.4.20
development of an efficient approach to construct fused polycyclic systems bearing a quaternarycarbon center represents a great challenge to synthetic chemistry. Herein, we report a Rh(III)-catalyzed [4 + 1] annulation of propargyl alcohols with various heterocyclic scaffolds under an air atmosphere. Diverse fused heterocycles containing a quaternarycarbon center were obtained in moderate to good
A RhIII-catalysed ortho C–H amination of phenidones under mild conditions was developed using N-alkyl-O-benzoyl-hydroxylamines as aminating agents, and with a cyclic hydrazine moiety as a directing group, yields of up to 97 % and a high functional group tolerance were observed. This strategy offers an alternative route for the synthesis of amino analogues of the 5-lipoxygenase inhibitor phenidone, and
Synthesis of pyrazolidinone fused cinnolines via the cascade reactions of 1-phenylpyrazolidinones with vinylene carbonate
作者:Na Li、Xinying Zhang、Xuesen Fan
DOI:10.1016/j.tetlet.2022.153984
日期:2022.8
Presented herein is an efficient synthesis of pyrazolidinone fused cinnolines through the cascade reactions of 1-phenylpyrazolidinones with vinylene carbonate. The reaction is initiated by C–H bond cleavage followed by C–C/C–N bonds formation and double C–O bonds cleavage. To our knowledge, this is the first example in which pyrazolidinone fused cinnoline derivatives free of redundant substituents