86-92-0Relevant articles and documents
Synthesis of Vinylcyclopropane-Fused Pyrazolone Derivatives by Sulfur Ylide-Initiated 1,6-Michael Addition-Cyclization Reactions
Li, Xiang,Liu, Yan-Qing,Kang, Jing-Wen,Chen, Fei-Yu,He, Xi-Guo,Yuan, Shan-Shan,Guo, Li,Peng, Cheng,Huang, Wei
, p. 4723 - 4730 (2018)
A highly diastereoselective cyclopropanation of α,β,γ,δ-unsaturated pyrazolones has been disclosed. This method allows for construction of a vinylcyclopropane-fused pyrazolone framework via a 1,6-addition/substitution sequence providing excellent regio- and chemoselectivity, good yields, broad functional group tolerance and gram-scale capacity. Moreover, the subsequent transformation of derivatives demonstrates great potential in building useful synthetic architectures.
Catalytic System-Controlled Divergent Reaction Strategies for the Construction of Diversified Spiropyrazolone Skeletons from Pyrazolidinones and Diazopyrazolones
Fang, Feifei,Han, Xu,Hu, Shulei,Li, Chunpu,Liu, Hong,Wang, Qian,Wang, Run,Zhou, Yu
supporting information, p. 21327 - 21333 (2021/08/20)
A catalytic system-controlled divergent reaction strategy was here reported to construct four types of intriguing spiroheterocyclic skeletons from simple and readily available starting materials via a precise chemical bond activation/[n+1] annulation cascade. The tetraazaspiroheterocyclic and trizazspiroheterocyclic scaffolds could be independently constructed by a selective N?N bond activation/[n+1] annulation cascade, a C(sp2)-H activation/[4+1] annulation and a novel tandem C(sp2)-H/C(sp3)?H bond activation/[4+1] annulation strategy, along with a broad scope of substrates, moderate to excellent yields and valuable transformations. More importantly, in these transformations, we are the first time to capture a N?N bond activation and a C(sp3)?H bond activation of pyrazolidinones under different catalytic system.
Electrochemical synthesis of versatile ammonium oxides under metal catalyst-, exogenous-oxidant-, and exogenous-electrolyte-free conditions
Yuan, Yong,Li, Liang-Sen,Zhang, Lin,Wang, Feng,Jiang, Lin,Zuo, Lin,Wang, Qi,Hu, Jian-Guo,Lei, Aiwen
supporting information, p. 2768 - 2771 (2021/03/23)
An electrochemical oxidative cross-coupling reaction between 2.5-substituted-pyrazolin-5-ones and ammonium thiocyanate has been developed, which resulted in a series of unprecedented cross-coupling products under metal catalyst-, exogenous-oxidant-, and exogenous-electrolyte-free conditions. It is worth noting that since the resulting cross-coupling products are nearly insoluble in MeCN, the pure product could be afforded without silica gel column purification. In addition, the prepared ammonium oxides are versatile building blocks for synthesizing functionalized pyrazole derivatives.