Formaldehyde → 8-bromo-3,6-di-tert-butyl-3,4-dihydro-2H-benzo[e][1,3]oxazine

Participants

Reaction Steps

A mixture of paraformaldehyde (19.99 g, 0.666 mol) and tert-butylamine (70.26 mL, 0.666 mol) in isopropanol (260 mL) was heated to gentle reflux under nitrogen for 75 minutes. A solution of 2-bromo-4-(tert-butyl)phenol (30.5 g, 0.133 mol) in isopropanol (40 mL) was then added and the mixture refluxed for a further 20 hours. The cooled reaction mixture was then concentrated to afford a yellow solid. The crude product was re-crystallized from methanol (100 mL) to give 8-bromo-3,6-di-tert-butyl-3,4-dihydro-2H-benzo[e][1,3]oxazine (36.74 g, 85% yield) as a cream crystalline solid.

Provenance & Evidence