反应详情

A solution of 0.145 g of [1R-(1R*,2E,S*),1β,3aα,7aβ]-octahydro-7a-methyl-1-[1-methyl-4-(2,2,4-trimethyl-1,3-dioxolan-4-yl)-2-butenyl]-4H-inden-4-ol in 9 ml of dry methylene chloride was treated with 0.250 g of anhydrous sodium acetate and 0.500 g of 2,2'-bipyridinium chlorochromate and the mixture stirred at room temperature for two hours. After this time, an additional 0.250 g of 2,2'-bipyridinium chlorochromate was added and the stirring continued for two more hours. After this time, 0.5 ml of isopropyl alcohol was added and the mixture stirred for 15 minutes, then diluted with water, and extracted with 3×50 ml of ether. The combined organic phases were washed with water, dried and evaporated to dryness. The residue obtained was purified by chromatography on silica gel, eluting with hexane-ethyl acetate (3:1) to give 0.134 g (93%) of pure [1R-(1R*,2E,S*),1β,3 aα,7aβ]-octahydro-7a-methyl-1-[1-methyl-4-(2,2,4-trimethyl-1,3-dioxolan-4-yl)-2-butenyl]-4H-inden-4-one, [α]D25 (c 0.2, ethanol).

1. stirringthe mixture stirred for 15 minutes
2. extractionextracted with 3×50 ml of ether
3. washThe combined organic phases were washed with water
4. customdried
5. customevaporated to dryness
6. customThe residue obtained
7. customwas purified by chromatography on silica gel
8. washeluting with hexane-ethyl acetate (3:1)