反应详情

温度

60 °C

NaOH (23 mL, 69 mmol, 3N aqueous solution) was added to a solution of 4-benzyloxy-2,2-dimethyl-2,3-dihydro-benzofuran-6-carboxylic acid methyl ester (77a) (7.18 g, 23 mmol) in MeOH (80 mL). The reaction mixture was heated to 60° C. for 3 hr, and concentrated in vacuo. The residue was diluted with H2O (100 mL) and washed with EtOAc (100 mL). The aqueous phase was acidified with 3N aqueous HCl to pH˜2 to form a white precipitate, which was filtered and dried to give a white solid (6.05 g, 88% yield). 1H NMR (400 MHz, DMSO-d6) δ 12.88 (s, 1 H) 7.38-7.48 (m, 4 H) 7.33 (t, J=7.07 Hz, 1 H) 7.14 (s, 1 H) 6.88 (s, 1 H) 5.17 (s, 2 H) 2.98 (s, 2 H) 1.42 (s, 6 H); LCMS for C18H18O5 m/z 299.10 (M+H)+.

1. concentrationconcentrated in vacuo
2. additionThe residue was diluted with H2O (100 mL)
3. washwashed with EtOAc (100 mL)
4. customto form a white precipitate, which
5. filtrationwas filtered
6. customdried