反应详情

温度

115 °C

1.0 g (3.3 mmol) of N-[2,2-dimethyl-6-hydroxychroman-4-yl]-N-ethyl-methanesulfonamide (Example 1g) was stirred at 80-90° C. for 30 min with 0.455 g of powdered potassium carbonate in 50 ml of DMA. 0.71 g (0.55 ml, 3.6 mmol) of ethyl 4-bromobutyrate was then added at 60° C. and the mixture was stirred at 115° C. for 90 min. It was then concentrated in vac., the residue was treated with water and aqueous hydrochloric acid, the mixture was taken up in EA, the solution was dried and concentrated, and the residue was chromatographed on silica gel using n-heptane/EA (3:1). Appropriate fractions were crystallized using petroleum ether, 0.74 g, m.p. 40-42° C.

1. concentrationIt was then concentrated in vac
2. addition, the residue was treated with water and aqueous hydrochloric acid
3. customthe solution was dried
4. concentrationconcentrated
5. customthe residue was chromatographed on silica gel
6. customAppropriate fractions were crystallized