Nitrile oxide cycloaddition reactions of alkenes or alkynes and nitroalkanes substituted with O-alkyloxime groups convertible to various functional groups

• DOI: 10.1016/j.tetlet.2020.152213
• Publication Date: 2020-07-06T15:10:18Z
• Authors: Nao Umemoto; Ayumi Imayoshi; Kazunori Tsubaki
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract Nitrile oxides, which are easily generated in situ from widely available nitroalkanes, can be used to directly access 2-isoxazoline heterocycles through 1,3-dipolar cycloaddition reactions with alkenes. These heterocycles are not only useful core fragments in pharmaceutical and agricultural chemistry, but also valuable building blocks convertible to multifunctional groups, such as β-hydroxy ketones. Herein, we have developed nitrile oxide cycloaddition reactions between nitrile oxides derived from O-alkyloxime-substituted nitroalkanes and various alkenes. This methodology can be applied to construct 2-isoxazolines possessing electron-withdrawing groups, which are difficult to access using the conventional approach.