Isobutyraldehyde → (4S)-4-Isobutyl-2-isopropyloxazolidine

Participants

Reaction Steps

A solution of (1S)-1-(hydroxymethyl)-3-methylbutylamine (Method B1b; 152 g, 1.3 mol) and isobutyraldehyde (118 mL, 1.3 mol, 1.0 equiv.) in toluene (1.5 L) was heated at the reflux temp. until the theoretical amount of water had been collected in a Dean-Stark trap (23.4 mL). The reaction mixture was concentrated by distillation to approximately 700 mL. The resulting mixture was cooled to room temp. and was concentrated under reduced pressure to a constant weight to give (4S)-2-isopropyl-4-isobutyl-1,3-oxazolidine as a pale yellow oil (223 g, 100%): 1H NMR (CDCl3) δ0.88-0.99 (m, 12H), 1.18-1.35 (m, 1H), 1.42-1.56 (m, 1H), 1.61-1.79 (m, 4H), 3.08 (t, J=7.4 Hz 1H), 3.20-3.34 (m, 1H), 3.85 (t, J=7.4 Hz, 1H), 4.18 (dd, J=7.3, 3.4 Hz, 1H).

Provenance & Evidence