反应详情

To the ester 130 (2.3 g, 6.0 mmol) in THF (80 mL) and MeOH (20 mL) was added NaOH solution (8 mL, 2N). The resulting mixture was stirred at room temperature for overnight following which the solvent was removed under reduced pressure and pH adjusted to 6 by the addition of cold dilute HCl. This was then extracted with DCM. The organic layer was washed with water, dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure to give 4-(3-(3-(tert-butoxycarbonylamino)-1-hydroxypropyl)phenoxy)butanoic acid (131). The product was directly utilized for the next transformation. Yield (1.94 g, 91%): 1H NMR (400 MHz, CDCl3) δ 7.18-7.22 (m, 1H), 6.84-6.90 (m, 2H), 6.77 (dd, J=7.6, 1.6 Hz, 1H), 5.18 (bs, 1H), 4.48-4.53 (m, 1H), 3.96 (t, J=6.4 Hz, 2H), 2.93-2.99 (m, 2H), 2.38 (t, J=7.4 Hz, 2H), 1.90-1.96 (m, 2H), 1.64-1.71 (m, 2H), 1.45 (s, 9H).

1. customwas removed under reduced pressure
2. additionpH adjusted to 6 by the addition of cold dilute HCl
3. extractionThis was then extracted with DCM
4. washThe organic layer was washed with water
5. dry with materialdried over anhydrous Na2SO4
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure