反应详情

温度

0 °C

3-(2-Benzyloxyethyl)-2,4-dioxo-3,9-diaza-bicyclo[3.3.1]nonane-9-carboxylic acid benzyl ester (Compound 3, 0.46 g, 1.11 mmol) was dissolved in methanol (15 mL). The mixture was cooled to 0° C., and NaBH4 (0.06 g, 1.66 mmol) was added in portions from the top. The reaction was stirred for 10 minutes at 0° C., and then 4N HCl in dioxane was added to obtain a pH in the range of 1 to 2, and the reaction was stirred overnight at room temperature. The methanol was evaporated, and the residue was dissolved in EtOAc and poured into NaHCO3 saturated aqueous solution, then extracted with EtOAc (3×10 mL). The combined extracts were washed with brine (10 mL), passed over a short plug of Na2SO4, and the solvents were evaporated to give Compound 4 (0.40 g, 85%, mixture of isomers) as a thick pale-yellow oil, which was of sufficiently good quality to be advanced to the next step without further purification. Rf (40% EtOAc/hexanes): 0.45.

1. customto obtain a pH in the range of 1 to 2
2. stirringthe reaction was stirred overnight at room temperature
3. customThe methanol was evaporated
4. dissolutionthe residue was dissolved in EtOAc
5. additionpoured into NaHCO3 saturated aqueous solution
6. extractionextracted with EtOAc (3×10 mL)
7. washThe combined extracts were washed with brine (10 mL)
8. customthe solvents were evaporated