[F:1][C:2]1[CH:3]=[CH:4][C:5]([C:8]2[N:12]=[C:11]([C:13]3[CH:18]=[C:17]([N+:19]([O-])=O)[CH:16]=[C:15]([C:22]#[N:23])[CH:14]=3)[O:10][N:9]=2)=[N:6][CH:7]=1.O.O.[Sn](Cl)Cl.ClCCl>C(O)C>[F:1][C:2]1[CH:3]=[CH:4][C:5]([C:8]2[N:12]=[C:11]([C:13]3[CH:14]=[C:15]([C:22]#[N:23])[CH:16]=[C:17]([NH2:19])[CH:18]=3)[O:10][N:9]=2)=[N:6][CH:7]=13-(5-fluoropyrid-2-yl)-5-(3-cyano-5-nitrophenyl)-1,2,4-oxadiazole (30 mg, 0.096 mmol) and tin(II) chloride dihydrate (109 mg, 0.48 mmol) in ethanol (1 mL) were sealed in a glass vial and then heated at 78 oC for 2 hours. The reaction was cooled and dichloromethane was added to the reaction mixture. The organic layer was washed with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated. Silica gel chromatography of the residue using hexanes:ethyl acetate:dichloromethane 1:3:4 followed by recrystallization using methanol afforded 6.3 mg (23%) of 3-(5-fluoropyrid-2-yl)-5-(3-amino-5-cyanophenyl)-1,2,4-oxadiazole: 1H NMR (CDCl3), δ (ppm): 8.69 (d, 1H), 8.25 (m, 1H), 7.89 (s, 1H), 7.76 (s, 1H), 7.61 (m, 1H), 7.11 (s, 1H), 4.17 (bs, 2H).
Wird geladen…
