反应详情

To a mixture of the hydroxyester compound which is 14-hydroxy-2-(1-methylethyl)-5,9,13-trimethyl-2,4,8,12-tetradecatetraenoic acid ethyl ester (71.0 mg, 0.20 mmol), S-collidine (26.7 mg, 0.22 mmol), lithium chloride (8.5 mg, 0.20 mmol) and dimethylformamide (1 ml) is added methanesulfonyl chloride (25.2 mg, 0.22 mmol) under nitrogen atmosphere while stirring on an ice-bath. The stirring is continued at the same temperature for 5 hours. After confirming disappearance of the starting compound, to the reaction mixture are added water and ethyl ether and the organic layer is separated. The organic layer is washed with water, dried (MgSO4) and concentrated. The resulting residue is chromatographed (n-hexane/ethyl acetate=10:1) on silica gel column to give the desired 14-chloro-2-(1-methylethyl)-5,9,13-trimethyl-2,4,8,12-tetradecatetraenoic acid ethyl ester (64.6 mg, 86%) from the desired fraction.

1. customthe organic layer is separated
2. washThe organic layer is washed with water
3. dry with materialdried (MgSO4)
4. concentrationconcentrated
5. customThe resulting residue is chromatographed (n-hexane/ethyl acetate=10:1) on silica gel column