反应详情

温度

65 °C

A suspension of 10.0 g of sodium acetate in 300 ml of chloroform and 300 ml of formaldehyde dimethylacetal is stirred with 19 ml of phosphorus oxychloride for one hour at a bath temperature of 65° C. After adding 10.0 g of 17α-hydroxy-16β-methyl-4,9(11)-pregnadiene-3,20-dione, another 19 ml of phosphorus oxychloride is added dropwise and the reaction solution is stirred for another 6.5 hours at 65° C. The cooled-off solution is treated with such an amount of a saturated soda solution that the aqueous phase is made permanently alkaline. The organic phase is separated, washed neutral and concentrated after drying. The crude product is purified on 700 g of silica gel with a hexane-ethyl acetate gradient (0-50% ethyl acetate), thus isolating 5.9 g of 17α-hydroxy-16β-methyl-6-methylene-4,9(11)-pregnadiene-3,20-dione, mp 157°-158° C.

1. additionThe cooled-off solution is treated with such an amount of a saturated soda solution that the aqueous phase
2. customThe organic phase is separated
3. washwashed neutral
4. concentrationconcentrated
5. customafter drying
6. customThe crude product is purified on 700 g of silica gel with a hexane-ethyl acetate gradient (0-50% ethyl acetate)