Tetrahydrofuran → tert-butyl N-((2R)-1-hydroxypropan-2-yl)carbamate

Participants

Reaction Steps

A solution of 24.3 g (0.323 mol) of 2(R)-aminopropanol is prepared in 450 ml of tetrahydrofuran and 8 ml of water. 32.6 g (0.323 mol) of triethylamine are added and a solution of 70.5 g (0.323 mol) of ditertbutyl dicarbonate (i.e. O[COC(CH3)3 ]2) in 150 ml of tetrahydrofuran is then added slowly. The reaction medium is stirred for 1 hour at room temperature and then concentrated under reduced pressure. The oily residue is taken up with 400 ml of ethyl ether and washed with 2 times 100 ml of a 0.1N solution of hydrochloric acid containing sodium chloride and then with a solution of sodium bicarbonate. The organic phase is dried over magnesium sulfate and concentrated under reduced pressure. The residue is taken up with 200 ml of cyclohexane and crystallized. The crude product is finally recrystallized from 350 ml of cyclohexane to give 49.3 g (yield=87%) of the expected product in the form of white crystals.

Provenance & Evidence