反应详情

温度

5 °C

The product from Step 2 (12.2 g) was suspended in dry dichloromethane (300 ml), cooled to 5° C. with stirring and dry triethylamine (18.1 ml) was added. The mixture was stirred for 0.25 hours and 2-bromobutyryl bromide (14.3 g) in dichloromethane (25 ml) was added dropwise over 0.5 hours at 10–18° C. The mixture was stirred for a further 0.5 hours then allowed to warm to ambient temperature for 2 hours and stored for 18 hours. Water was added and the organic phase was separated, washed with water (three times), dried over magnesium sulphate then evaporated under reduced pressure to give the required product as a dark yellow oil, 17.4 g, 1H NMR (CDCl3) δ: 1.04(3H, t); 1.62(6H, s); 1.96(2H, m); 2.10(2H, m); 2.38(2H, m); 3.66(2H, t); 4.12(1H, t); 6.44(1H, s).

1. stirringThe mixture was stirred for 0.25 hours
2. stirringThe mixture was stirred for a further 0.5 hours
3. temperatureto warm to ambient temperature for 2 hours
4. customthe organic phase was separated
5. washwashed with water (three times)
6. dry with materialdried over magnesium sulphate
7. customthen evaporated under reduced pressure