Yield:635702-31-7 1350 g

Reaction Conditions:

with hydroxylamine hydrochloride;triethylamine in methanol at 60; for 0.666667 h;

Steps:

19 Example 19 4-bromo-2-fluoro-N-hydroxybenzimidamide 24

To 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 H₂0 (30 L), and lots of off-white solid was separated out, and then filtered, the filter cake was washed with water (10 L x 2) and 1350 g wet 4-bromo-2-fluoro-N-hydroxybenzimidamide 24 was obtained with 96% purity.

References:

WO2014/140073,2014,A1 Location in patent:Page/Page column 16; 32