反应详情

A solution of 10 g (50 mmol) the ester from step (a), t-butyldimethylsilyl chloride (8.25 g, 55 mmol) and imidazole (4.76 g, 70 mmol) in 100 mL of DMF was stirred under argon for 1 h. The solution was poured into 100 mL of water and extracted with ether (3×50 mL). The combined ether solutions were extracted with 20 mL of water. The organic layer was dried and evaporated giving 18 g of an oil which was purified by column chromatography using 0-2% ethyl acetate in hexane yielding 14.4 g of the product as a colorless oil (91%); 1H NMR (CDCl3) δ0.218 (s,6H), 0.995 (s,9H), 3.81 (t,2H), 4.56 (t,2H), 7.05-7.65 (m,4H). ##STR13##

1. extractionextracted with ether (3×50 mL)
2. extractionThe combined ether solutions were extracted with 20 mL of water
3. customThe organic layer was dried
4. customevaporated