A novel protocol for the efficient activation of the Beckmannrearrangement utilizing the readily available sulfuryl fluoride (SO2F2 gas) is reported. The substrate scope of this methodology has been demonstrated by 37 examples with good to nearly quantitative isolated yields in a short time. A tentative mechanism was proposed involving formation and elimination of sulfonyl ester.
报道了一种利用容易获得的硫酰氟(SO 2 F 2气体)有效激活贝克曼重排的新方案。该方法的底物范围已通过37个实例证明,并在短时间内获得了良好至近乎定量的分离产率。提出了一种尝试性的机制,涉及形成和消除磺酰基酯。
Synthesis of 5-Vinyl-2-isoxazolines by Palladium-Catalyzed Intramolecular <i>O</i>-Allylation of Ketoximes
作者:Rodney A. Fernandes、Ashvin J. Gangani、Arpita Panja
DOI:10.1021/acs.orglett.1c01897
日期:2021.8.20
An efficient method for the synthesis of 5-vinyl-2-isoxazolines by Pd-catalyzed intramolecular O-allylation of ketoximes has been developed. The reaction involves Pd(0)-catalyzed π-allyl formation via leaving group ionization or Pd(II)-catalyzed allylic C–H activation followed by intramolecular nucleophilic oxime oxygen attack. This methodology has been elaborated to various value-added products by
Copper(0)/PPh<sub>3</sub>-Mediated Bisheteroannulations of <i>o</i>-Nitroalkynes with Methylketoximes Accessing Pyrazo-Fused Pseudoindoxyls
作者:Huanxin Meng、Zhenhua Xu、Zhonghua Qu、Huawen Huang、Guo-Jun Deng
DOI:10.1021/acs.orglett.0c02180
日期:2020.8.7
A copper(0)/PPh3-mediated cascade bisheteroannulation reaction of o-nitroalkynes with methylketoximes has been developed that provides viable access to a diverse range of pyrazo-fused pseudoindoxyl compounds. Synthetically useful functional groups including sensitive C–I bonds are compatible with this system. Mechanistic studies suggest a reaction cascade involving sequential PPh3-mediated deoxygenative
The azirine formation by LAH reduction of oximes has been extended to several types, such asandThe result was satisfactory to generalization of this reaction.
通过LAH还原肟形成的叠氮基已扩展为多种类型,例如和,其结果对于该反应的一般化是令人满意的。
SOCl<sub>2</sub>/<font>β</font>-Cyclodextrin: A New and Efficient Catalytic System for Beckmann Rearrangement and Dehydration of Aldoximes Under Aqueous Condition
作者:Dipak Patil、Dipak Dalal
DOI:10.1080/00397911.2011.592747
日期:2013.1.1
Abstract A rapid and efficient synthesis of amides via Beckmannrearrangement of ketoximes and dehydration of aldoximes to corresponding nitriles with good to excellent yields has been carried out in the presence of SOCl2/β-cyclodextrin under aqueous conditions. The β-cyclodextrin has been recovered and reused. GRAPHICAL ABSTRACT