[CH3:1][O:2][C:3]1[CH:4]=[C:5]([C:8]([O:11]COC)=[CH:9][N:10]=1)[CH:6]=[O:7].Cl>C1COCC1.O>[OH:11][C:8]1[C:5]([CH:6]=[O:7])=[CH:4][C:3]([O:2][CH3:1])=[N:10][CH:9]=1To a solution of 2-methoxy-5-(methoxymethoxy)isonicotinaldehyde (10 g, 0.05 mol) in THF (100 mL) was added 3 N HCl (150 mL). The reaction was stirred at 50° C. for 30 min, cooled to rt, and diluted with water (100 mL). The mixture was neutralized to pH 7-8 and extracted with EtOAc (200 mL) three times. The organic layer was dried over Na2SO4 and concentrated to give 5-hydroxy-2-methoxyisonicotinaldehyde (4.2 g, 55%) as a yellow solid. 1H NMR (400 MHz; DMSO) δ=10.31 (s, 1H), 8.03 (s, 1H), 6.89 (s, 1H), 3.80 (s, 3H).
Wird geladen…