反应详情

To a solution of ethyl 3-((2-(4-chlorophenyl)imidazo[1,2-a]pyridin-3-yl)methyl)-1,2,4-oxadiazole-5-carboxylate (10.5 mmol, 4.0 g) in MeOH (50 mL) was cooled to 0° C., and 99% NH2NH2.H2O (62.8 mmol, 3.2 g) was then added dropwise. In the period of addition, lots of white precipitate was generated, kept stirring for 15 mins, the white solid was collected by filtration. The white solid was dispersed into MeOH again, sonicated for 10 mins, filtered, to give the final product (3.3 g, 86.0%). m/e+=369 (M+H+). 1H NMR (400 MHz, in DMSO-d6): δ 10.9-10.5 (1H, D, brd, NH), δ 8.44-8.42 (1H, D, d, J=6.8 Hz, ArH), δ 7.87-7.85 (2H, D, dd, J=6.4, 1.6 Hz, ArH), δ 7.67-7.64 (1H, D, d, J=9.2 Hz, ArH), δ 7.56-7.54 (2H, D, dd, J=6.4, 1.6 Hz, ArH), δ 7.38-7.25 (1H, D, m, ArH), δ 5.01-4.75 (2H, D, brd, NH2), δ 4.75 (2H, D, s, CH2).

1. additionIn the period of addition, lots of white precipitate
2. filtrationthe white solid was collected by filtration
3. additionThe white solid was dispersed into MeOH again
4. customsonicated for 10 mins
5. filtrationfiltered