Methanol → methyl 2-(5-methoxy-1H-indol-3-yl)acetate

Beteiligte Stoffe

Reaktionsschritte

A reaction mixture containing 2-(5-methoxy-1H-indol-3-yl)acetic acid (0.5 g, 2.44 mmol) and BOP-Cl (0.62 g, 2.44 mmol) in 7 mL of anhydrous CH2Cl2 was treated with triethyl amine (0.49 g, 4.87 mmol) and allowed to stir at ambient temperature for 5 min. The mixture was then combined with anhydrous methanol (0.34 mL) and continuously stirred overnight at room temperature. Following dilution with dichloromethane (30 mL), the organic solution was washed with water (2×15 mL), dried over Na2SO4, and filtered (using a commercial phase separator syringe with attached drying cartridge). The organic filtrate was collected and concentrated in vacuo and the crude ester was purified by flash chromatography on silica gel (ethyl acetate/hexane gradient) to afford the title compound as viscous yellow oil, which permanently crystallized upon storage at −20° C. (453 mg, 85%). C12H13NO3, Mr=219.24; 1H NMR (400 MHz, DMSO-d6) d: 3.60 (s, 3H), 3.70 (s, 2H), 3.74 (s, 3H), 6.72 (dd, J=2.4/8.8 Hz, 1H), 6.96 (d, J=2.4 Hz, 1H), 7.19 (d, J=2.4 Hz, 1H), 7.23 (d, J=8.8 Hz, 1H), 10.77 (s, 1H); LCMS (ESI) tR: 1.95 min (>99%, UV254), m/z: 220.1 [M+1]+.

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