反应详情

A mixture of ethyl 3-(5-bromobenzothiazol-2yl- methyl)-4-oxo-3-H-phthalazin-1-ylacetate (15.0 g) and dioxane (150 ml) was brought to solution by warming on a steam bath and to this solution was added a solution of 10% potassium hydroxide (20 ml) in ethanol (50 ml.). The resulting dark purple solution was stirred at room temperature for 2 hours and concentrated to remove excess dioxane and ethanol. The concentrate was diluted with water (100 ml) and the resulting solution was washed with ether (2×100 ml). The aqueous layer was collected and acidified to pH 2.0 by addition of concentrated HCl. The precipitated solid was crystallized from methylene chloride/ethanol (400 ml/40 ml) to obtain the product (Yield 7.65 g; m.p. 214° C.).

1. temperatureby warming on a steam bath and to this solution
2. concentrationconcentrated
3. customto remove excess dioxane and ethanol
4. additionThe concentrate was diluted with water (100 ml)
5. washthe resulting solution was washed with ether (2×100 ml)
6. customThe aqueous layer was collected
7. additionacidified to pH 2.0 by addition of concentrated HCl
8. customThe precipitated solid was crystallized from methylene chloride/ethanol (400 ml/40 ml)
9. customto obtain the product (Yield 7.65 g; m.p. 214° C.)