Triethylamine → (2-hydroxy-ethyl)-(1H-indol-7-ylmethyl)-carbamic acid benzyl ester

Participants

Reaction Steps

To a solution of 2-[(1H-indol-7-ylmethyl)-amino]-ethanol (4.4 g) in 1,2-dichloroethane (40 mL) was added triethylamine (4.85 mL, 34.6 mmol) followed by benzyl chloroformate (3.57 mL, 25.34 mmol). The mixture was allowed to stir at room temperature for 2 hours. The mixture was quenched by addition of water (20 mL), and 1.0 M sodium hydroxide (10 mL). The organic layer was separated and the aqueous layer extracted with 1,2-dichloroethane (20 mL). The combined organic extracts were washed with 1.0 M hydrochloric acid (20 mL), water (20 mL), dried over anhydrous sodium sulfate and evaporated to dryness. The residue was purified by silica gel chromatography, eluting with 20% ethyl acetate in hexanes to 40% ethyl acetate in hexanes to afford (2-hydroxy-ethyl)-(1H-indol-7-ylmethyl)-carbamic acid benzyl ester (2.79 g, 52% combined yield for two steps) as a colorless oil. 1H NMR (CDCl3) 400 MHz δ: 9.97 (br s, 1H), 7.75-6.9 (m, 8H), 6.54 (br s, 1H), 5.21 (s, 2H), 4.9-4.6 (m, 3H), 3.85-3.57 (m, 2H), 3.55-3.23 (m, 3H); LCMS M+H=325.

Provenance & Evidence