反应详情

5-(Methoxymethylene)-2,2-dimethyl-1,3-dioxane-4,6-dione (7 g, 38 mmole), described by Bihlmayer et al., supra, was suspended in ethanol (70 ml). The suspension was stirred vigorously while being subjected to the addition of ethanethiol (12.85 g, 200 mmole). The mixture was heated at reflux until all the starting material had been consumed, as indicated by thin layer chromatography (silica gel plates, 30% ethyl acetate in hexane). The volatile portion of the reaction mixture was removed by distillation under reduced pressure. The residue was purified by high pressure liquid chromatography (HPLC, 20% ethyl acetate in hexane, v/v). The purest fractions were combined. The solvent was removed under reduced pressure. The residue was crystallized to give 5.0 g of the title compound; mp 52°-54° C.; NMR (CDCl3) δ 1.45 (t, 3H), 1.7 (s, 6H), 3.02 (q, 2H), 9.0 (s, 1H); IR (CHCl3) 1720, 1700 cm-1.

1. temperatureThe mixture was heated
2. temperatureat reflux until all the starting material
3. customhad been consumed
4. customThe volatile portion of the reaction mixture was removed by distillation under reduced pressure
5. customThe residue was purified by high pressure liquid chromatography (HPLC, 20% ethyl acetate in hexane, v/v)
6. customThe solvent was removed under reduced pressure
7. customThe residue was crystallized