[O:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH:4]([C:11]([O:13][C:14]2[CH:23]=[CH:22][C:17]([C:18]([O:20]C)=[O:19])=[C:16]([O:24][CH3:25])[CH:15]=2)=[O:12])[CH2:3][CH2:2]1.O.O[Li].O>C1COCC1>[O:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH:4]([C:11]([O:13][C:14]2[CH:23]=[CH:22][C:17]([C:18]([OH:20])=[O:19])=[C:16]([O:24][CH3:25])[CH:15]=2)=[O:12])[CH2:3][CH2:2]1To a stirred solution of methyl 4-(4-chromanoyloxy)-2-methoxybenzoate (260 mg, 0.82 mmol) in THF:H2O (4 mL:0.8 mL) was added LiOH.H2O (172 mg, 4.1 mmol). The reaction was heated to 45° C. over 12 h and then cooled to ambient temperature. The solvent was removed under reduced pressure. The crude solid was passed through a small plug of silca gel packed in 90:10 CH2Cl2 :MeOH(NH3) and eluted with same. The solvent was removed under reduced pressure to afford 4-(4-chromanoyloxy)-2-methoxybenzoic acid as a foam.
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