反应详情

400 mg of ethyl 4-(4-tert-butoxycarbonylcyclohexyl)benzoate (1.2 mmol, 1 eq) are placed in 6 mL of a 2/1 mixture of tetrahydrofuran and methanol. The reaction medium is cooled using an ice bath, and 202 mg of lithium hydroxide monohydrate (4.81 mmol, 4 eq.) dissolved in 2 mL are added and stirring is continued for 18 hours. The reaction medium is evaporated and acidified with aqueous 6% sulfur dioxide solution. After stirring for 1 hour, the solid obtained is filtered off by suction, and washed successively with water, ethanol and ethyl acetate. The residue is chromatographed on silica gel, eluting with a gradient of methanol in dichloromethane ranging from 3% to 5%. 125 mg of 4-(4-tert-butoxycarbonylcyclohexyl)benzoic acid are obtained.

1. temperatureThe reaction medium is cooled
2. additionare added
3. customThe reaction medium is evaporated
4. stirringAfter stirring for 1 hour
5. customthe solid obtained
6. filtrationis filtered off by suction
7. washwashed successively with water, ethanol and ethyl acetate
8. customThe residue is chromatographed on silica gel
9. washeluting with a gradient of methanol in dichloromethane ranging from 3% to 5%