[CH3:1][O:2][CH2:3][CH2:4][NH:5][C:6]1[CH:7]=[C:8]([C:16]([O:18]C)=[O:17])[C:9]2[C:14]([CH:15]=1)=[CH:13][CH:12]=[CH:11][CH:10]=2.CO.[Li+].[OH-]>C1COCC1>[CH3:1][O:2][CH2:3][CH2:4][NH:5][C:6]1[CH:7]=[C:8]([C:16]([OH:18])=[O:17])[C:9]2[C:14]([CH:15]=1)=[CH:13][CH:12]=[CH:11][CH:10]=2Methyl 3-{[2-(methyloxy)ethyl]amino}-1-naphthalenecarboxylate (1 eq.) from the previous step was taken up in a 2:1 (v/v) mixture of MeOH:THF (0.08 M). To this solution was then added LiOH (1.0 M aq. solution, 3.4 eq.) and the resulting cloudy solution was vigorously stirred at RT for 16 h. The volatiles were then removed in vacuo and the pH of the residue was carefully adjusted to ˜2 with 1 N aq. HCl before it was extracted with EtOAc. The combined organic extracts were washed further with water and brine, dried over Na2SO4 and filtered. Concentration of the filtrate in vacuo afforded the title compound as a yellow solid.
Wird geladen…
