反应详情

Sodium hydroxide 2M (10 mL) was added to a solution of the 6-cyclobutylmethoxy-5-pyrrolidin-1-yl-pyrazine-2-carboxylic acid methyl ester (2.2 g, 7.4 mmol) in a (1:1) mixture of methanol and tetrahydrofuran (30 mL), the reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated in vacuo and the residue was dissolved in ether (30 mL) and extracted with water (50 mL), the aqueous layer was washed with ether (2×50 mL) until only product remained in the aqueous layer. The aqueous layer was cooled to 0° C. and acidified with concentrated hydrochloric acid until precipitation was observed. The precipitate was filtered and dried in vacuo to afford 6-cyclobutylmethoxy-5-pyrrolidin-1-yl-pyrazine-2-carboxylic acid as a cream solid 1.65 g (80% yield) LC@215 nm; Rt 1.98: 93%, m/z (ES+): 278 (M+H).

1. concentrationThe reaction mixture was concentrated in vacuo
2. dissolutionthe residue was dissolved in ether (30 mL)
3. extractionextracted with water (50 mL)
4. washthe aqueous layer was washed with ether (2×50 mL) until only product
5. temperatureThe aqueous layer was cooled to 0° C.
6. customacidified with concentrated hydrochloric acid until precipitation
7. filtrationThe precipitate was filtered
8. customdried in vacuo