反应详情

To a stirring suspension of imidazo[1,2-a]pyridine-3-carboxylic acid (1) (71 mg, 0.39 mmol) in anhydrous dichloromethane (2 mL) was added dropwise oxalyl chloride (173 uL, 1.98 mmol). Then, a drop of anhydrous N,N-dimethylformamide was added and the reaction mixture was stirred at room temperature for 30 minutes. The solvent was concentrated. A stirring mixture of the acid chloride and 5-(azetidin-1-yl)-3-(4-methyl-3-nitrophenyl)-1,2,4-oxadiazole (109) (85 mg, 0.29 mmol) in anhydrous pyridine (2 mL) was stirred at room temperature for 30 minutes. The crude product was purified on silica gel using 10% MeOH in dichloromethane to give N-(5-(5-(azetidin-1-yl)-1,2,4-oxadiazol-3-yl)-2-methylphenyl)imidazo[1,2-a]pyridine-3-carboxamide (F77). 1H NMR (400 MHz, CD2Cl2) δ 10.10 (s, 1H), 9.51-9.48 (m, 1H), 8.65 (s, 1H), 7.94 (d, J=1.6 Hz, 1H), 7.86-7.83 (m, 1H), 7.71 (dd, J=1.6, 7.6 Hz, 1H), 7.64-7.60 (m, 1H), 7.43 (d, J=8.0 Hz, 1H), 7.27-7.24 (m, 1H), 4.26-4.22 (m, 4H), 2.48-2.40 (m, 2H), 2.34 (s, 3H). MS m/z 374.15 (M+1)+.

1. concentrationThe solvent was concentrated
2. stirringwas stirred at room temperature for 30 minutes
3. customThe crude product was purified on silica gel using 10% MeOH in dichloromethane