[OH:1][C:2]1[CH:9]=[CH:8][C:5]([CH2:6][OH:7])=[CH:4][C:3]=1[O:10][CH3:11].C(N(CC)CC)C.[C:19](Cl)(=[O:21])[CH3:20]>C(Cl)Cl>[C:19]([O:1][C:2]1[CH:9]=[CH:8][C:5]([CH2:6][OH:7])=[CH:4][C:3]=1[O:10][CH3:11])(=[O:21])[CH3:20]A partial solution of 4-hydroxy-3-methoxybenzyl alcohol (1.23 g, 8 mmol), triethylamine (810 mg, 1.12 mL, 8 mmol) and 32 mL of dry CH2Cl2 was chilled in an ice bath. To the cold mixture was added dropwise acetyl chloride (628 mg, 570 μL, 8 mmol). The mixture was stirred at ice bath temperature 1 for one hour. Stirring at room temperature was allowed to take place overnight. The reaction mixture was diluted with CH2Cl2 and extracted with 1N HCl, water and saturated NaCl. The organic layer was dried over MgSO4, filtered and concentrated. Column chromatography on silica gel using CH2Cl2/MeOH (98:2, v/v) gave 548 mg (35%) of CO as a clear oil: Rf=0.22 (hexanes/ethyl acetate, 6:4 v/v); 1HNMR (CDCl3) δ 7.00 (d, 4J=1.5 Hz, 1H), 6.99 (d, 3J=8.5 Hz, 1H), 6.89 (dd, 3J=8.0 Hz, 4J=1.5 Hz, 1H), 5.27 (s, 2H), 4.66 (s, 2H), 3.83 (s, 3H) and 2.30 (s, 3H). Exact mass (FAB+) calculated for C10H12O4[M+] 196.0736. found 196.0739.
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