Sulfuric Acid → 2,3,4,5-Tetrahydro-1,4-benzoxazepin-5-one

Participants

Reaction Conditions

Reaction Steps

To 4-chromanone (50 g, 340 mmol) in acetic acid (670 ml) was added sodium azide (66.31 g, 1.02 mol) and conc. sulfuric acid (100 ml) dropwise at 0° C. The mixture was heated to 50° C. for 4 h and then cooled to room temperature. The mixture was poured onto ice (1 l) and basified with conc. ammonium hydroxide. The mixture was stirred for 24 h and the solids were collected by filtration (30.43 g, 55%), MSm/z 164 [M+H]+.

Provenance & Evidence