[CH3:1][O:2][C:3](=[O:11])[CH2:4][CH2:5][CH2:6][CH2:7][C:8]([OH:10])=O.[Br:12][C:13]1[CH:21]=[CH:20][C:16]([C:17](O)=[O:18])=[C:15]([CH2:22]C(O)=O)[CH:14]=1.Cl>C1COCC1>[Br:12][C:13]1[CH:14]=[C:15]2[C:16](=[CH:20][CH:21]=1)[C:17](=[O:18])[O:10][C:8]([CH2:7][CH2:6][CH2:5][CH2:4][C:3]([O:2][CH3:1])=[O:11])=[CH:22]2To a stirred mixture of adipic acid monomethyl ester (9.27 g, 57.9 mmol, 1.50 equiv.) in THF (50 mL) was added N,N′-carbonyldiimidazole (9.39 g, 57.9 mmol, 1.50 equiv.) and the mixture was stirred at room temperature. After stirring for 30 min, the reaction mixture was cooled to 0° C. followed by dropwise addition of 4-bromo-2-(carboxymethyl)benzoic acid (10.0 g, 38.6 mmol) in THF (25 mL). The reaction was stirred gradually from 0° C. to room temperature for 48 h. Upon completion of the reaction, 0.5 N HCl (25 mL) solution was added and extracted with EtOAc (2×25 mL). The organic layer was washed with aqueous sat. NaHCO3, dried over Na2SO4, filtered and evaporated to dryness. The residue was purified by column chromatography on silica gel eluting with 0-15% EtOAc/hexanes to give 1.5 g of methyl 5-(6-bromo-1-oxo-1H-isochromen-3-yl)pentanoate as a white solid.
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