Facile synthesis and herbicidal activities of new isoxazole derivatives via 1,3-dipolar cycloaddition reaction

Abstract

A series of cycloadducts via 1,3-dipolar cycloaddition reactions of generated nitrile oxides with N-(4-chloro-2-fluorophenyl) maleimides were described. The reaction of N-(4-chloro-2-fluorophenyl) maleimides with nitrile oxides gave 3,5-diaryl-3a,6a-dihydropyrroio[3,4-d]isoxazole-4,6-diones through syn-addition pattern. The title compounds were characterized by 1H NMR, IR, MS, and elemental analysis or HRMS. The single crystal structure of 6i was determined by X-ray diffraction. The herbicidal activities of the title compounds were evaluated. Some of them exhibited certain herbicidal activities against barnyardgrass and rape.