Fluoroacetic acid → 4-bromo-2-(fluoromethyl)-6-nitro-1H-benzo[d]imidazole
Reaction equation
[Br:1][C:2]1[CH:7]=[C:6]([N+:8]([O-:10])=[O:9])[CH:5]=[C:4]([NH2:11])[C:3]=1[NH2:12].[F:13][CH2:14][C:15](O)=O>C1(C)C=CC=CC=1>[Br:1][C:2]1[C:3]2[N:12]=[C:15]([CH2:14][F:13])[NH:11][C:4]=2[CH:5]=[C:6]([N+:8]([O-:10])=[O:9])[CH:7]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a 250 mL round bottomed flask was added 3-bromo-5-nitrobenzene-1,2-diamine (6.75 g, 29.1 mmol) and 2-fluoroacetic acid (4.54 g, 58.2 mmol) in Toluene (100 mL). The solution was heated to reflux 48 h. The reaction was found to be incomplete so an additional equivalent of acid (2.25 g) was added and solution was heated 6 hours. The mixture was allowed to cool and was evaporated. The residue was dissolved in 20 ml of DCM and was filtered through a sintered glass funnel where a brown precipitate (5.5 g, 69%) was isolated to obtain 4-bromo-2-(fluoromethyl)-6-nitro-1H-benzo[d]imidazole (6.01 g, 21.93 mmol, 75% yield). 1H NMR (400 MHz, DMSO-d6) δ ppm 5.69 (s, 1H) 5.81 (s, 1H) 8.33 (d, J=2.02 Hz, 1H) 8.49 (br. s., 1H); LC/MS: MS (ES+) m/e 275 [M+H]+.