Selective Synthesis of 3‐(α‐Fluorovinyl)indoles and 3‐Acylindoles via the Cascade Reactions of 1‐Phenylpyrazolidinones with α,α‐Difluoromethylene Alkynes
作者:Yujie Yang、Na Li、Jie Zhao、Yuqin Jiang、Xinying Zhang、Xuesen Fan
DOI:10.1002/adsc.202100441
日期:2021.7.20
Presented herein is a selective synthesis of 3-(α-fluorovinyl)indoles and 3-acylindoles via the coupling of 1-phenylpyrazolidinones with α,α-difluoromethylene alkynes. Mechanistically, the formation of 3-(α-fluorovinyl)indoles is resulted from a cascade process including Rh(III)-catalyzed ortho-C−H bond cleavage, regioselective triple bond insertion, pyrazolidinone ring-opening, indole ring-formation
Construction of Pyridazine Analogues <i>via</i>
Rhodium-mediated C-H Activation
作者:Chao Yang、Feifei Song、Jiean Chen、Yong Huang
DOI:10.1002/adsc.201700905
日期:2017.10.25
Herein a rhodium (III)‐mediated catalysis was demonstrated for approaching the structurally divergent N,N‐bicyclic pyridazine analogues. The pyrazolidinone moiety was used to direct the ortho C−H activation and this led to a general synthesis of benzopyridazine analogues with satisfactory yields. The crucial effect of the base was illustrated in the sequential dehydration process. For mechanistic insight
Synthesis of Dihydroquinolinone Derivatives via the Cascade Reaction of <i>o</i>-Silylaryl Triflates with Pyrazolidinones
作者:Mengyang Shen、Jie Zhao、Yuanshuang Xu、Xinying Zhang、Xuesen Fan
DOI:10.1021/acs.joc.1c01814
日期:2021.11.5
Presented herein is a novel synthesis of dihydroquinolinone derivatives through an unprecedented cascadereaction of o-silylaryl triflates with pyrazolidinones. Mechanistically, the formation of the title products is believed to involve a cascade procedure including in situ formation of aryne and its addition with pyrazolidinone followed by N–N bond cleavage and intramolecular C–C bond formation/annulation
Synthesis of Pyrazolo[1,2‐a]cinnolines
<i>via</i>
Rhodium(III)‐Catalyzed [4+2] Annulation Reactions of Pyrazolidinones with Sulfoxonium Ylides
作者:Shulei Hu、Xu Han、Xiong Xie、Feifei Fang、Yong Wang、Abdusaid Saidahmatov、Hong Liu、Jiang Wang
DOI:10.1002/adsc.202100324
日期:2021.7
A method to synthesize pyrazolo[1,2-a]cinnolines via rhodium(III)-catalyzed C−H activation of pyrazolidinones and subsequent [4+2] annulation of sulfoxonium ylides was developed. 5-Substituted or 5,10-disubstituted pyrazolo[1,2-a]cinnolines could be obtained by slightly adjusting the reaction conditions. Gram-scale synthesis and practical transformations proved the practicability of this method. The
Selective Synthesis of Pyrazolo[1,2-<i>a</i>]pyrazolones and 2-Acylindoles via Rh(III)-Catalyzed Tunable Redox-Neutral Coupling of 1-Phenylpyrazolidinones with Alkynyl Cyclobutanols
作者:Yuanshuang Xu、Mengyang Shen、Xinying Zhang、Xuesen Fan
DOI:10.1021/acs.orglett.0c01475
日期:2020.6.19
An unprecedented divergent synthesis of pyrazolo[1,2-a]pyrazolones and 2-acylindoles via Rh(III)-catalyzed [4 + 1] or [3 + 2] annulation of 1-phenylpyrazolidinones with alkynyl cyclobutanols through redox-neutral multiple bond activation by using −NH and −OH units as directing groups is presented. Notably, different annulation reactions were selectively achieved by simply adjusting the reaction conditions
通过Rh(III)催化1-苯基吡唑烷二酮与炔基环丁醇通过氧化还原-中性多键的环化反应,空前地合成吡唑并[1,2- a ]吡唑并酮和2-酰基吲哚。提出了通过使用-NH和-OH单元作为导向基团的活化。值得注意的是,通过简单地调节反应条件选择性地实现了不同的环化反应。这些方法具有操作简单,容易获得的底物和高区域选择性/化学选择性等特点,可以在相关领域广泛应用。