N-bromobutanimide → 12-bromo-2,10-dichloro-12H-5,7-dioxadibenzo[a,d]cyclooctene

Participants

Reaction Conditions

Reaction Steps

To a solution of 2,10-dichloro-12H-dibenzo[d,g][1,3]-dioxocin (21.4 g, 76.1 mmol) and N -bromosuccinimide (13.5 g, 76.1 mmol) in tetrachloromethane (275 mL) was added azo-bisisobutyronitrile (200 mg, 1.2 mmol). The mixture was heated at 80° C. for 24 h. Another 3×azobisisobutyronitrile (200 mg, 1.2 mmol) was added within the 24 h. The mixture was filtrated and the solution phase concentrated in vacuo. The residue was added dichloromethane (30 mL) and ether (100 mL). The mixture was filtered and the solution phase concentrated in vacuo. The residue was submitted to flash chromatography eluting with heptane/ethyl acetate (3:1) to give 7.4 g (27%) of 12-bromo-2,10-dichloro-12H-5,7-dioxa-dibenzo[a,d]cyclooctene.

Provenance & Evidence