Carbon tetrabromide → cis 4-(2-Fluoro-5-bromobenzyloxy)but-2-enyl bromide
Reaction equation
[F:1][C:2]1[CH:14]=[CH:13][C:12]([Br:15])=[CH:11][C:3]=1[CH2:4][O:5][CH2:6][CH:7]=[CH:8][CH2:9]O.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C(Br)(Br)(Br)[Br:36]>C(OCC)C>[F:1][C:2]1[CH:14]=[CH:13][C:12]([Br:15])=[CH:11][C:3]=1[CH2:4][O:5][CH2:6]/[CH:7]=[CH:8]\[CH2:9][Br:36]Participants
5
Procedure
In a 100 ml round bottom flask 4-(2-fluoro-5-bromobenzyloxy)but-2-en-1-ol (2.145 g, 7.80 mmol) was dissolved in diethyl ether under a nitrogen atmosphere. Triphenylphosphine (2.66 g, 10.1 mmol) and then carbon tetrabromide (3.36 g, 10.1 mmol) were added to the reaction mixture. The resulting mixture was stirred for six hours at ambient temperature. A white precipitate formed during the stirring. The progress of the reaction was monitored by thin layer chromatography. The solution was filtered and the filtrate was evaporated to give a thick oil. The desired title intermediate was further purified by liquid chromatography.