Efficient synthesis of isoxazoles and isoxazolines from aldoximes using Magtrieve™ (CrO2)
作者:Sandeep Bhosale、Santosh Kurhade、Uppuleti Viplava Prasad、Venkata P. Palle、Debnath Bhuniya
DOI:10.1016/j.tetlet.2009.04.073
日期:2009.7
Treatment of aldoximes 1 with Magtrieve™ (CrO2) in presence of dipolarophile 3 or 4, furnished a variety of isoxazolines 5a–u and isoxazoles 6a–q as 1,3-dipolar cycloaddition (1,3-DC) products (38 examples; 63–90% isolated yields). In situ formation of a nitrile oxide intermediate was confirmed through isolation of the dimerization product furoxane 2a in absence of any dipolarophile. The methodology
[2 + 2 + 1] Cycloaddition of <i>N</i>-tosylhydrazones, <i>tert</i>-butyl nitrite and alkenes: a general and practical access to isoxazolines
作者:Liang Ma、Feng Jin、Xionglve Cheng、Suyan Tao、Gangzhong Jiang、Xingxing Li、Jinwei Yang、Xiaoguang Bao、Xiaobing Wan
DOI:10.1039/d1sc02352g
日期:——
N-tosylhydrazones has not been examined. Herein, we report the first demonstrations of [2 + 2 + 1] cycloaddition reactions that allow the facile synthesis of isoxazolines, employing N-tosylhydrazones, tert-butyl nitrite (TBN) and alkenes as reactants. This process represents a new type of cycloaddition reaction with a distinct mechanism that does not involve the participation of nitrile oxides. This