Trifluoroacetic acid → (R)-2-(4-Methoxybenzoylamino)-2-phenylethylazide

Participants

Reaction Conditions

Reaction Steps

(R)-2-(Boc-amino)-2-phenylethyl azide (47.8 g, 0.182 mole) was added to trifluoroacetic acid (500 mL) with stirring and ice-water bath cooling. The cooling bath was removed, the reaction was allowed to stir 1 h, and the solvent was removed in vacuo at 35° C. water bath temperature. The residue was co-evaporated with toluene to give a weight of 75.0 g. The residue was dissolved in 1,4-dioxane (500 mL) and water (500 mL), with ice-water bath cooling, and then potassium carbonate (113.5 g, 0.82 mol), and anisoyl chloride (37.3 g, 0.219 mol) were added. Another portion of 1,4-dioxane (300 mL) was added to facilitate stirring. After stirring over the weekend, water (1 L) was added. The mixture was cooled to −15° C., and vacuum filtered to collect a white solid. The solid was washed with water, air dried, and then dried under vacuum at 50° C. for 4 h to afford 46.3 g (86%) of the title compound.

Provenance & Evidence