反应详情

Lithium octanolate (prepared in advance from 13.02 g (100.00 mmol) of 1-octanol and 69 ml (110.00 mmol) of a 1.6 molar n-butyllithium solution in n-hexane at 0° C. in 40 ml of tetrahydrofuran) and 25.49 g (100.00 mmol) of 2,5-dibromo-3-fluoropyridine are refluxed for 7 hours in 40 ml of tetrahydrofuran. The mixture is subsequently partitioned between aqueous sodium chloride solution and ether, and the ether phase is washed twice with aqueous sodium chloride solution, dried over sodium sulfate, filtered and freed from solvent. Chromatographic purification (silica gel/hexane: ethyl acetate 9:1) gives 18.19 g (59.80 mmol) of 5-bromo-3-fluoro-2-octyloxypyridine. ##STR23##

1. customThe mixture is subsequently partitioned between aqueous sodium chloride solution and ether
2. washthe ether phase is washed twice with aqueous sodium chloride solution
3. dry with materialdried over sodium sulfate
4. filtrationfiltered
5. customChromatographic purification (silica gel/hexane: ethyl acetate 9:1)