[CH3:1][C:2]1[CH:3]=[CH:4][CH:5]=[C:6]([OH:13])[C:7]=1[C:8]([O:10][CH2:11][CH3:12])=[O:9].O.[OH-].[Li+].S(OC)(O[CH3:21])(=O)=O>C1COCC1.C(OCC)C>[CH3:21][O:13][C:6]1[CH:5]=[CH:4][CH:3]=[C:2]([CH3:1])[C:7]=1[C:8]([O:10][CH2:11][CH3:12])=[O:9]To a solution of ethyl 6-methylsalicylate (1.27 g, 6.97 mmol) in THF (35 mL) was added lithium hydroxide monohydrate (0.594 g, 14.2 mmol) followed by dimethyl sulfate (1.00 mL, 10.6 mmol). The resultant mixture was heated to reflux for 1 hour then cooled to room temperature. The mixture was diluted with diethyl ether (70 mL), washed with saturated aqueous NaHCO3 (4×10 mL), dried (MgSO4) and concentrated. Purification of the crude material by column chromatography on silica gel (9:1 hexanes-EtOAc) provided 1.23 g (91%) of ethyl 2-methoxy-6-methylbenzoate as a white solid. 1H NMR (CDCl3) δ 1.38 (t, 3H, J=7.2 Hz), 2.30 (s, 3H), 3.82 (s, 3H), 4.40 (q, 2H, J=7.2 Hz), 6.76 (d, 1H, J=8.4 Hz), 6.79 (d, 1H, J=7.8 Hz), 7.23 (dd, 1H, J=7.8, 8.4 Hz).
読み込み中…
