Oxime-Mediated Oxychlorination and Oxybromination of Unactivated Olefins
作者:Kui-Yong Dong、Hai-Tao Qin、Feng Liu、Chen Zhu
DOI:10.1002/ejoc.201403538
日期:2015.3
An oxime-mediatedoxychlorination and oxybromination of unactivatedolefins relying on palladium catalysis has been developed. A wide range of chlorinated and brominated isoxazolines has been synthesized in moderate to good yields. To demonstrate the value of the method, the brominated isoxazoline has been further converted to other useful synthetic feedstock.
Potassium iodate ($$\hbox {KIO}_{3}$$) as a novel reagent for the synthesis of isoxazolines: evaluation of antimicrobial activity of the products
作者:Sumana Y Kotian、P M Abishad、K Byrappa、K M Lokanatha Rai
DOI:10.1007/s12039-019-1622-9
日期:2019.6
isoxazolines has been reported. Aryl aldoximes were made to react with alkenes in the presence of \(\hbox KIO}_3}\) as the oxidising agent. This new reagent has been useful as an oxidant in the synthesis of isoxazoline and its function is attributed to the generation of nitrile oxide, which is an important intermediate for the synthesis of the valuable heterocycle like isoxazoline. Graphical Abstract
A general and efficient oxyhalogenation of unsaturated ketoximes has been achieved through copper catalysis with diethyl bromomalonate, N-chlorosuccinimide, and N-iodosuccinimide, yielding 5-chloromethyl, 5-bromomethyl, and 5-iodomethyl isoxazolines in good to excellent yields.
4‐chlorobenzonitrile oxide (2) which was generated in situ with acrylo nitrile (3), vinyl acetate (4) and allyl bromide (5) as dipolarphile afforded the new cycloadducts 6a, 7a, and 8a compounds, respectively. Reactivity and regiochemistry of these reactions were investigated using activation energy calculations and density functional theory‐based reactivity indexes. The theoretical 13C NMR chemical shifts
原位生成的4-氯苄腈氧化物(2)与丙烯腈(3),乙酸乙烯酯(4)和烯丙基溴(5)作为偶极亲电子的反应分别提供了新的环加合物6a,7a和8a化合物。使用活化能计算和基于密度泛函理论的反应指数对这些反应的反应性和区域化学进行了研究。通过轨距不变原子轨道方法获得的环加合物的理论13 C NMR化学位移与观测值相当。
Intramolecular Electrochemical Oxybromination of Olefins for the Synthesis of Isoxazolines in Batch and Continuous Flow
A new electrochemical method for the synthesis of 2-isoxazolines is reported. The reaction operates under atmospheric conditions and tolerates air and moisture. The use of potassium bromide as both electrolyte and bromine source precludes the need for toxic, air-sensitive inorganic oxidants or transition metal catalysts.