反应详情

To a solution of 1.27 g of 3-carboxymethyl-5-(3-fluoro-4-phenyl-α-methylbenzyl)-1,2,4-oxadiazole obtained in Example 39 in 20 ml of dry methanol was added a drop of conc. sulfuric acid. The mixture was allowed to stand at room temperature overnight and then concentrated to dryness under reduced pressure. The solution of the residue in benzene was washed successively with a sodium bicarbonate solution and water, dried over sodium sulfate and evaporated. The residue was chromatographed over silica gel using benzene to give 0.95 g of 3-methoxycarbonylmethyl-5-(3-fluoro-4-phenyl-α-methylbenzyl)-1,2,4-oxadiazole, nD25 1.5618.

1. concentrationconcentrated to dryness under reduced pressure
2. washThe solution of the residue in benzene was washed successively with a sodium bicarbonate solution and water
3. dry with materialdried over sodium sulfate
4. customevaporated
5. customThe residue was chromatographed over silica gel