C([O:4][C:5]1[C:12]([O:13][CH3:14])=[CH:11][CH:10]=[C:9]([Br:15])[C:6]=1[CH:7]=[O:8])(=O)C.C(=O)(O)[O-].[Na+]>CO>[OH:4][C:5]1[C:12]([O:13][CH3:14])=[CH:11][CH:10]=[C:9]([Br:15])[C:6]=1[CH:7]=[O:8]To the aldehyde 11 (17.7 g) in aqueous methanol (125 mL) was added sodium bicarbonate (7.6 g, 1.1 eq.) and the turbid bright yellow solution stirred for 2 hours. The solution was acidified, extracted with dichloromethane and the solvent removed in vacuo to afford a yellow solid. The product was recrystallized from ethyl acetate/hexane to afford yellow crystals (14.7 g, 98%): m.p. 105.6-106.4° C., lit19 m.p. 102-103° C.; EIMS m/z 232 (M+, 81Br), 230 (M+, 79Br), 186, 107, 79, 54, 32; Anal. Calcd. For C8H7O3Br: C, 41.59; H, 3.05. Found: C, 41.83; H, 3.27.
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