反应详情

2,6-Dichlorobenzamidoxime (1.0 g) was dissolved in pyridine and m-nitrobenzoyl chloride (0.91 gm, 1.0 molar equivalent) was added. The solution was stirred at room temperature for 1 h under nitrogen, then heated at 90° C. for 4 h. The solution was cooled to room temperature, and poured into ice water. The pH of the solution was adjusted to approximately pH 10 with 2M aqueous sodium carbonate solution. The mixture was extracted with ether and the organic layer was dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to dryness. The residue was dissolved in ethyl acetate. Addition of hexanes to the solution gave 3-(2,6-dichlorophenyl)-5-(3-nitrophenyl)-1,2,4-oxadiazole as a white solid (0.69 g). NMR (300 MHz, DMSO-d6): 8.52 (s, 1H), 8.38 (d, 1H), 8.18 (d, 1H), 7.78 (t, 1H), 7.57 ppm (m, 3H). LC-MS tr=38.2 min (Method W) MH++NA=359

1. temperatureheated at 90° C. for 4 h
2. temperatureThe solution was cooled to room temperature
3. extractionThe mixture was extracted with ether
4. dry with materialthe organic layer was dried over anhydrous sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure to dryness
7. dissolutionThe residue was dissolved in ethyl acetate
8. additionAddition of hexanes to the solution