反应详情

To a stirred solution of 4,5-dihydro-2-(3-hydroxyphenyl)-4(R)-phenyloxazole (3.3 g, 13.8 mmol) in N,N-dimethylformamide (30 ml) was added sodium hydride (60% in mineral oil, 0.62 g, 16 mmol) portionwise over 5 min. at ambient temperature. The mixture was stirred for 1 hour, and then a solution of 2-bromo-1-(tert-butyldimethylsilyloxy)ethane (4.94 g, 21 mmol) in N,N-dimethylformamide (5 ml) was added dropwise over 5 min. and the reaction mixture stayed overnight. The reaction mixture was partitioned between ethyl acetate (50 ml) and water (50 ml), the aqueous layer was separated, extracted with ethyl acetate (2×50 ml) and the combined organic phase washed with 1N HCl (100 ml), aqueous 4% NaHCO3 solution (100 ml) and brine (100 ml), dried (MgSO4) and evaporated. The resulting residue was purified by column chromatography on silica gel eluting with ethyl acetate/n-hexane (=1:6) to afford 1-(tert-butyldimethylsilyloxy)-2-[3-(4,5-dihydro-4(R)-phenyloxazol-2-yl)phenoxy]ethane (4.7 g, 86%) as a colorless oil.

1. waitthe reaction mixture stayed overnight
2. customThe reaction mixture was partitioned between ethyl acetate (50 ml) and water (50 ml)
3. customthe aqueous layer was separated
4. extractionextracted with ethyl acetate (2×50 ml)
5. washthe combined organic phase washed with 1N HCl (100 ml), aqueous 4% NaHCO3 solution (100 ml) and brine (100 ml)
6. dry with materialdried (MgSO4)
7. customevaporated
8. customThe resulting residue was purified by column chromatography on silica gel eluting with ethyl acetate/n-hexane (=1:6)