C[C:2]1[CH:3]=[C:4]([CH:9]=[CH:10][CH:11]=1)[C:5]([O:7]C)=O.[N:12]1[CH:17]=[CH:16][C:15]([CH3:18])=[CH:14][CH:13]=1.[C:19](=O)(O)[O-].[Na+]>O1CCCC1>[C:3]1([CH3:19])[CH:2]=[CH:11][CH:10]=[CH:9][C:4]=1[C:5](=[O:7])[CH2:18][C:15]1[CH:16]=[CH:17][N:12]=[CH:13][CH:14]=1Methyl 3-methylbenzoate (6.0 g, 40 mmol), tetrahydrofuran (50 mL), and 4-picoline (4.1 g, 44 mmol) were stirred at −78° C. under an atmosphere of nitrogen. Sodium (bis)trimethylsilylamide 1.0 M in tetrahydrofuran (88 mL, 88 mmol) was added dropwise. The mixture was allowed to warm to room temperature, stirred for 16 hours and then was poured into saturated aqueous sodium bicarbonate solution. The mixture was then extracted with ethyl acetate (3×50 mL). The combined organics were washed with brine (2×50 mL), dried over magnesium sulfate, and concentrated. The product was recrystallized from ethyl acetate/hexane to yield a light yellow solid (5.7 g, 67%), mp 118.0–119.0° C.; 1H NMR (acetone-d6/300 MHz) 8.50 (m, 2H), 7.90 (m, 2H), 7.44 (m, 2H), 7.29 (m, 2H), 4.45 (s, 2H), 2.41 (s, 3H); ESHRMS m/z 212.1067 (M+H, C14H13NO requires 212.1075); Anal. Calc'd for C14H13NO: C, 79.59; H, 6.20; N, 6.63. Found: C, 79.54; H, 6.30; N, 6.56.
Wird geladen…
