[Synthesis]
a) Preparation of 2-(N-methylamino)benzyl alcohol
Lithium aluminum hydride (0.76 g, 0.02 mol) was suspended in anhydrous tetrahydrofuran (40 mL) under argon protection. To this suspension, an anhydrous tetrahydrofuran solution of N-methylphthalamic acid (1.51 g, 0.01 mol) was slowly added. The reaction mixture was refluxed for 1 hour and then the reaction was quenched by the addition of ice water (50 mL). The mixture was filtered through a diatomaceous earth pad and the filter cake was washed thoroughly with dichloromethane (50 mL). The organic layer was separated and the aqueous layer was further extracted with dichloromethane (50 mL). All organic layers were combined, washed with brine (30 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure. The resulting pale yellow oil was purified by silica gel column chromatography (Wakogel C-200, 50 g, eluent n-hexane:ethyl acetate=2:1) to afford the colorless oil (2-(methylamino)phenyl)methanol (1.18 g, 86% yield).
1H-NMR (270 MHz, CDCl3): δ 2.87 (3H, s), 3.00-3.10 (1H, br.s), 4.64 (2H, s), 6.65-6.69 (2H, m), 7.05 (1H, d, J=7.2 Hz), 7.23-7.29 (1H, m). |