反应详情

(S)-3,5-dichloro-4-(2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)-2-hydroxyethyl)pyridine 1-oxide (500 mg, 1.2 mmol) is dissolved in CH2Cl2 (15 ml), DMAP (180 mg, 1.8 mmol) and 2-bromoacetyl chloride (243 mg, 1.55 mmol) are added. The mixture is stirred at RT for 2 hours, then is diluted with CH2Cl2 (50 ml) and quenched with HCl 1N aqueous solution (50 ml). The two phases are separated, and the organic phase is washed with HCl 1N aqueous solution (2×50 ml), dried over Na2SO4 and evaporated under vacuum. The crude contains a mixture of the title compound (bromoacetoxy-derivative) and an undesired compound (chloroacetoxy-derivative), in a cumulative amount of 550 mg. The compound undergoes the next step without any further purification. MS/ESI+ 541.17 [MH]+.

1. customquenched with HCl 1N aqueous solution (50 ml)
2. customThe two phases are separated
3. washthe organic phase is washed with HCl 1N aqueous solution (2×50 ml)
4. dry with materialdried over Na2SO4
5. customevaporated under vacuum
6. additiona mixture of the title compound (bromoacetoxy-derivative)
7. customwithout any further purification