反应详情

To prepare Hex-3-yne-2,5-dioxe: Chromium trioxide (100 g) in concentrated sulphuric acid (90 ml) and water (550 ml) was added with vigorous stirring over 2 hours to hex-3-yne-2,5-diol (28 g) and 5-hydroxyhex-3-yn-2-one (28 g) in acetone (400 ml) at -5° to 0°. After 1 hour, water (150 ml) was added and the solution extracted with ether. The extract was washed (aqueous NaHCO3), dried (MgSO4) and distilled to give crude hex-3-yne-2,5-dione (3-6 g), B.P. 50° (bath) at 0.15 m Hg and 5-hydroxy-hex-3-yne-2-one (B.P 50°-75° at 0.2 mm Hg) 23 g.

1. extractionthe solution extracted with ether
2. washThe extract was washed (aqueous NaHCO3)
3. dry with materialdried (MgSO4)
4. distillationdistilled