反应详情

温度

90 °C

A mixture of 2-(3-bromo-4-fluorobenzoyl)-3-hydroxypyridine (2.96 g), O-t-butyl hydroxylamine hydrochloride (1.88 g) and acetic acid (50 mL) was stirred at 90° C. for 14 hours. The reaction mixture was concentrated in vacuo, which was subjected to addition with ethyl acetate and water. The ethyl acetate solution was washed with aqueous NaHCO3 and a saturated aqueous saline solution, successively, which was dried (magnesium sulfate), followed by distilling off the solvent under reduced pressure. The residue was subjected to purification by means of a silica gel column (ethyl acetate--hexane) to afford (E)-2-(3-bromo-α-t-butoxyimino-4-fluorobenzyl)-3-hydroxypyridine (1.10 g) and (Z)-2-(3-bromo-α-t-butoxyimino-4-fluorobenzyl)-3-hydroxypyridine (1.97 g) (compounds 17 and 16).

1. concentrationThe reaction mixture was concentrated in vacuo, which
2. additionwas subjected to addition with ethyl acetate and water
3. washThe ethyl acetate solution was washed with aqueous NaHCO3
4. dry with materiala saturated aqueous saline solution, successively, which was dried (magnesium sulfate)
5. distillationby distilling off the solvent under reduced pressure
6. customThe residue was subjected to purification by means of a silica gel column (ethyl acetate--hexane)