Bromine → 9-Bromomethyl-6,11-dihydro-11-oxodibenz[b,e]oxepin

Reaction equation

[CH3:1][C:2]1[CH:3]=[CH:4][C:5]2[CH2:11][O:10][C:9]3[CH:12]=[CH:13][CH:14]=[CH:15][C:8]=3[C:7](=[O:16])[C:6]=2[CH:17]=1.[Br:18]Br>BrCCBr.[W]>[Br:18][CH2:1][C:2]1[CH:3]=[CH:4][C:5]2[CH2:11][O:10][C:9]3[CH:12]=[CH:13][CH:14]=[CH:15][C:8]=3[C:7](=[O:16])[C:6]=2[CH:17]=1

Participants

Procedure

To a stirred and irradiated (Tungsten lamp) solution of 2.0 gm of the 9-methyl compound of Step B in 5 ml of 1,2-dibromoethane, add a solution of 1.7 gm of bromine in 5 ml of 1,2-dibromoethane dropwise over a period of 1 hour at 150° C. Cool the reaction mixture, pour into ice water and extract with water and dry over sodium sulfate. Concentrate to dryness and crystallize the residue from isopropyl ether to obtain the title product.