反应详情

温度

90 °C

(see Eur. J. Med. Chem.-Chim. Ther. 1977, 12, 531) 54.8 g (400 mMol) 6-methoxy-3-pyridinecarbaldehyde (Aldrich) are dissolved in 180 ml of acetic acid. 63.8 g (778 mMol) sodium acetate are added portionwise (slightly exothermic). Then a solution of 30 ml (582 mMol) of bromine in 120 ml of acetic acid is added dropwise during 30 min. The mixture is stirred for 5 h at 90° C., then cooled to RT and concentrated partially in vacuo. The residue is diluted with icewater, neutralized to pH 7.5 with 4 N NaOH and extracted with 4 portions of EtOAc. The organic layers are washed twice with water and brine, dried (Na2SO4) and concentrated in vacuo. Column chromatography (SiO2; CH2Cl2) of the resulting oil and crystallization from CH2Cl2/hexane gives the title compound: mp: 94-95° C.

1. temperaturecooled to RT
2. concentrationconcentrated partially in vacuo
3. additionThe residue is diluted with icewater
4. extractionextracted with 4 portions of EtOAc
5. washThe organic layers are washed twice with water and brine
6. dry with materialdried (Na2SO4)
7. concentrationconcentrated in vacuo
8. customColumn chromatography (SiO2; CH2Cl2) of the resulting oil and crystallization from CH2Cl2/hexane