Carbon tetrabromide → 2-(Bromomethyl)-1-iodo-4-(trifluoromethyl)benzene
Reaction equation
[C:1]([Br:5])(Br)(Br)Br.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[I:25][C:26]1[CH:31]=[CH:30][C:29]([C:32]([F:35])([F:34])[F:33])=[CH:28][C:27]=1CO>C(Cl)Cl>[Br:5][CH2:1][C:27]1[CH:28]=[C:29]([C:32]([F:34])([F:35])[F:33])[CH:30]=[CH:31][C:26]=1[I:25]Participants
Procedure
Carbon tetrabromide (1.86 g; 5.6 mmol) and triphenylphosphine (1.47 g; 5.6 mmol) were added successively to a stirred solution of [2-iodo-5-(trifluoromethyl)phenyl]methanol (Intermediate 10, 1.13 g; 3.74 mmol) in CH2Cl2 (25 mL) at 0° C. under N2. The reaction was stirred at room temperature for 48 h. A second equivalent of carbon tetrabromide (1.2 g; 3.74 mmol) and triphenylphosphine (0.98 g; 3.74 mmol) was added and the reaction was stirred an additional 14 h. The solvent was removed in vacuo and the residue was purified by flash chromatography on silica gel (0-25% EtOAc/hexanes gradient) to afford 2-(bromomethyl)-1-iodo-4-(trifluoromethyl)benzene as a clear oil. 1H NMR (CDCl3, 500 MHz): δ 8.02 (d, J=8.2 Hz, 1 H), 7.73 (d, J=1.8 Hz, 1 H), 7.26 (dd, J=8.3, 1.8 Hz, 1 H), 4.64 (s, 2 H).
Workup
- stirringthe reaction was stirred an additional 14 h
- customThe solvent was removed in vacuo
- customthe residue was purified by flash chromatography on silica gel (0-25% EtOAc/hexanes gradient)
Sources & evidence
- ORD record
- ord-ea18b92bb4204159a52a4d644757baa4
- Source dataset
- uspto-grants-2010_08
- Patent number
- US07781426B2
Reaction notes
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