反应详情

To a solution of 1-(tert-butoxycarbonylamino-methyl)-2-isobutyl-cyclopropanecarboxylic acid methyl ester (9.1 g, 31.9 mmol) in MeOH (260 mL) was added a solution of LiOH (3.34 g, 79.7 mmol) in water (80 mL). The reaction mixture was heated to reflux for 3 hours and cooled to room temperature. Excess of solvent was removed and the residue was dissolved in water (100 mL). The aqueous solution was washed with ether, acidified to pH=3 with 2N HCl and extracted with EtOAc (2×150 mL). The combined organic phase was washed with brine, dried (Na2SO4) and evaporation of the solvent gave 8.4 g (97%) of 1-(tert-butoxycarbonylamino-methyl)-2-isobutyl-cyclopropanecarboxylic acid as a colorless oil: 1H NMR (300 MHz, CD3OD) δ 0.71 (dd, J=4.0, 6.4 Hz, 1H), 0.95 (t, J=6.4 Hz, 6H), 1.35 (m, 1H), 1.43 (s, 1H), 1.49-1.55 (m, 1H), 1.64-1.69-(m, 2H) 3.23 (d, J=14.2 Hz, 1H), 3.40 (d, J=14.2 Hz, 1H).

1. temperatureThe reaction mixture was heated
2. temperatureto reflux for 3 hours
3. customExcess of solvent was removed
4. dissolutionthe residue was dissolved in water (100 mL)
5. washThe aqueous solution was washed with ether
6. extractionextracted with EtOAc (2×150 mL)
7. washThe combined organic phase was washed with brine
8. customdried
9. custom(Na2SO4) and evaporation of the solvent