[I:1][C:2]1[CH:9]=[CH:8][CH:7]=[C:6]([F:10])[C:3]=1[CH:4]=O.Cl.[NH2:12][OH:13].[OH-].[Na+].Cl>O.CCO>[I:1][C:2]1[CH:9]=[CH:8][CH:7]=[C:6]([F:10])[C:3]=1[CH:4]=[N:12][OH:13]To a mixture of 2-iodo-6-fluorobenzaldehyde (45 mmol) in H2O (22.5 ml), EtOH (22.5 ml), and ice (20 g) was added hydroxylamine hydrochloride (3.19 g, 49.5 mmol, 1.1 eq.). Then, 112.5 mmol of 50% NaOH (4.5 g in 4.5 ml H2O, 2.5 eq.) was added with stirring. Enough ice to keep the temperature at 25-30° C. was added. The reaction was stirred for 2 h, acidified with conc. HCl to pH 4 (ice was added to keep the temperature at 25-30° C.), and extracted with Et2O. The combined organic solution was washed with brine, dried (MgSO4), filtered, and concentrated. The residue was chromatographed on silica gel using ethyl acetate in hexanes (5%-10%) to give 2-iodo-6-fluorobenzaldehyde oxime (7.06 g, 59% over 2 steps) as an oil that solidified over time.
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