反应详情

A solution of 0.1 mol of 2-(octylphenyl)-5-(2-hydroxy-5-oxaoctyloxy)-6-fluoropyridine (prepared by heating optically active 1,2-epoxy-5-oxaoctane, obtainable from malic acid, with 2C in the presence of dry potassium carbonate and methyl ethyl ketone as solvent) in methylene chloride is cooled to -40° C., and 0.11 mol of DAST is added dropwise thereto with exclusion of moisture. The reaction mixture is subsequently stirred for 12 hours with slow warming to room temperature. The reaction mixture is then hydrolyzed with ice cooling and washed with dilute sodium hydroxide solution and several times with water. The mixture is dried over magnesium sulfate, the solvent is removed on a rotary evaporator, and the crude product is purified by chromatography and by crystallization, giving optically active 2-(4-octyloxyphenyl)-5-(2-fluoro-5-oxaoctyloxy)-6-fluoropyridine.

1. washhydrolyzed with ice cooling and washed with dilute sodium hydroxide solution and several times with water
2. dry with materialThe mixture is dried over magnesium sulfate
3. customthe solvent is removed on a rotary evaporator
4. customthe crude product is purified by chromatography and by crystallization