[OH-].[K+].[C:3]([C:6]1[CH:15]=[C:14]2[C:9]([CH:10]=[CH:11][C:12]([C:16]([O:18]C)=[O:17])=[CH:13]2)=[CH:8][CH:7]=1)(=[O:5])[CH3:4].Cl>O.CO.C(Cl)Cl>[C:3]([C:6]1[CH:15]=[C:14]2[C:9]([CH:10]=[CH:11][C:12]([C:16]([OH:18])=[O:17])=[CH:13]2)=[CH:8][CH:7]=1)(=[O:5])[CH3:4]
A solution of KOH 70 mg, 10 mmol) in water (3.5 mL) was added dropwise to a cooled solution of the ester 168 (640 mg, 2.81 mmol) in MeOH (10 mL) and CH2Cl2 (10 mL) at 0° C. After allowing the mixture to warm to room temperature and stirring for 96 h, excess CH2Cl2 and water were added. The aqueous portion was acidified (pH 2) with 2N HCl and the resulting white precipitate was extracted with EtOAc (×2). The combined EtOAc extracts were washed with water, brine, and dried, to give 7-acetyl-2-naphthoic acid (169). (575 mg, 96%) as a colorless solid. A sample was recrystallised from petroleum ether/CH2Cl2/Et2O: mp 224-228° C.; 1H NMR: (CDCl3) 8 (CO2H not observed) 8.82 (s, 1H), 8.60 (s, 1H), 8.23 (dd, J=8.6, 1.6 Hz, 1H), 8.18 (dd, J=8.7, 1.7 Hz, 1H), 7.97 (c, J=8.7 Hz, 2H), 2.76 (s, 3H). Anal. (C13H10O3) C, H.
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