反应详情

A solution of ethyl 3-[4-benzyloxyphenyl)-2-hydroxypropanoate (5.0 g, 16.6 mmol) (prepared in a similar manner as described in Ref: WO95/18125) in dry dimethyl formamide (5 mL) was added to a suspension of sodium hydride (0.1 g, 41.6 mmol) (60% dispersion in oil) in dry dimethyl formamide (3 mL) at 0° C. and stirring was continued for further 1 h. To the above reaction mixture n-butyl bromide (3.4 g, 24.0 mmol) was added at 0° C. and stirring was continued for 10 h at ca. 25° C. Water (30 mL) was added and extracted with ethyl acetate 2×50 mL). The combined ethyl acetate layer was washed with water (50 mL), brine (25 mL), dried (Na2SO4), filtered and the solvent was evaporated. The residue was chromatographed over silica gel using a mixture of ethyl acetate and the pet. ether (1:9) as an eluent to afford the title compound (0.7 g, 20%) as an oil.

1. stirringstirring
2. waitwas continued for 10 h at ca. 25° C
3. extractionextracted with ethyl acetate 2×50 mL)
4. washThe combined ethyl acetate layer was washed with water (50 mL), brine (25 mL)
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. customthe solvent was evaporated
8. customThe residue was chromatographed over silica gel using
9. additiona mixture of ethyl acetate