Triethylamine → HCID 22823403, compound

Participants

Reaction Steps

To a solution of 1.16 g (5 mmol) of Boc-L-leucine and 0.70 ml (5 mmol) of triethylamine in 12 mL of tetrahydrofuran (dried over sodium/lead alloy) at -15° was added 0.66 mL (5 mmol) of i-butyl chloroformate. After 10 min., 1.19 g (5 mmol) of 7-amino-3-phenylcoumarin suspended in 6 mL of tetrahydrofuran was added. The mixture was stirred at -15° for 30 min. and then overnight at room temperature. The reaction mixture was then reduced to dryness on a rotary evaporator at 1.6 kPa and 60°. The residue was taken up in 100 mL of ethyl acetate, washed twice with 25-mL portions of 1 N aqueous sodium bicarbonate and twice with 25-mL portions of saturated sodium chloride, dried over anhydrous magnesium sulfate, filtered, and evaporated. The residue was dried overnight at room temperature and 3 Pa to yield 1.91 g. (84.8%) of crude product as a yellow foam which was purified by chromatography on a silica gel column eluted first with methylene chloride and then with 5% methanol in methylene chloride. Product recovery was 66.5%.

Provenance & Evidence