[Br:1][C:2]1[CH:9]=[CH:8][C:5]([C:6]#[N:7])=[C:4]([F:10])[CH:3]=1.Cl.[NH2:12][OH:13].CCN(CC)CC>CO>[Br:1][C:2]1[CH:9]=[CH:8][C:5]([C:6](=[NH:7])[NH:12][OH:13])=[C:4]([F:10])[CH:3]=1To a solution of 4-Bromo-2-fluorobenzonitrile 11 (800 g, 4 mol, 1 eq), hydroxylamine hydrochloride (695 g, 10 mol, 2.5 eq) in MeOH (2 L, 2.5 vol) was added Et3N (485 g, 4.8 mol, 1.2 eq), then the mixture was stirred at 60° C. for 40 min and checked by HPLC (no nitrile remaining) Reaction was then quenched by H2O (30 L), and lots of off-white solid was separated out, and then filtered, the filter cake was washed with water (10 L×2) and 1350 g wet 4-bromo-2-fluoro-N-hydroxybenzimidamide 24 was obtained with 96% purity
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