反应详情

Sodium borohydride (25 mg, 0.66 mmol) was added to a solution of (E)-2-chloro-4-[3-(3-hydroxyphenyl)-1-oxoprop-2-en-1-yl]benzoic acid methyl ester (Example 91; 316 mg, 1 mmol) in methanol (3 mL). The solution was stirred at room temperature for 3 h, then acetone (1 mL) was added and the solution was stirred for a further 10 min. The solvent was evaporated, ethyl acetate (15 mL) was added and the solution was washed with 0.5N hydrochloric acid solution (10 mL) and brine. Each of the aqueous layers was extracted in turn with ethyl acetate (10 mL). The combined organic layers were dried (MgSO4), filtered, evaporated and the resulting solid was triturated with diethyl ether to furnish rac.-(E)-2-chloro-4-[1-hydroxy-3-(3-hydroxyphenyl)prop-2-en-1-yl]benzoic acid methyl ester (310 mg, 97% yield) as a colorless solid.

1. stirringthe solution was stirred for a further 10 min
2. customThe solvent was evaporated
3. additionethyl acetate (15 mL) was added
4. washthe solution was washed with 0.5N hydrochloric acid solution (10 mL) and brine
5. extractionEach of the aqueous layers was extracted in turn with ethyl acetate (10 mL)
6. dry with materialThe combined organic layers were dried (MgSO4)
7. filtrationfiltered
8. customevaporated
9. customthe resulting solid was triturated with diethyl ether