反应详情

To a stirred solution 5-benzyloxy-6-hydroxy-2-[1-(4-trifluoromethyl-phenyl)-cyclopentylmethyl]-pyrimidine-4-carboxylic acid tert-butyl ester (243) (250 mg, 0.53 mmol) in the mixture of tetrahydrofuran-water (2:1, 10 mL) was added lithium-hydroxide monohydrate (477 mg, 11.36 mmol) and the reaction mixture was refluxed for 20 h. Very small amounts of the starting ester remained. Silica thin layer chromatography was performed (50% ethyl acetate in hexane, Rf=0.1). Volatiles were evaporated, water added (10 mL) and the aqueous part was extracted with ethyl acetate (2×3 0 mL). The ethyl acetate part was thereafter discarded and the aqueous part was acidified with 1N HCl to a pH of about 5-6. The acidified aqueous part was extracted with ethyl acetate (3×30 mL), dried and concentrated to get 5-benzyloxy-6-hydroxy-2-[1-(4-trifluoromethyl-phenyl)-cyclopentylmethyl]-pyrimidine-4-carboxylic acid (244) (250 mg, 93.13%) as an off-white solid.

1. additionwas added lithium-hydroxide monohydrate (477 mg, 11.36 mmol)
2. temperaturethe reaction mixture was refluxed for 20 h
3. customVolatiles were evaporated
4. additionwater added (10 mL)
5. extractionthe aqueous part was extracted with ethyl acetate (2×3 0 mL)
6. extractionThe acidified aqueous part was extracted with ethyl acetate (3×30 mL)
7. customdried
8. concentrationconcentrated