Boron tribromide → 5-cyano-4-fluoro-2-hydroxy-N-(3-nitro-benzyl)-benzamide
Reaction equation
[C:1]([C:3]1[C:4]([F:24])=[CH:5][C:6]([O:22]C)=[C:7]([CH:21]=1)[C:8]([NH:10][CH2:11][C:12]1[CH:17]=[CH:16][CH:15]=[C:14]([N+:18]([O-:20])=[O:19])[CH:13]=1)=[O:9])#[N:2].B(Br)(Br)Br>ClCCl>[C:1]([C:3]1[C:4]([F:24])=[CH:5][C:6]([OH:22])=[C:7]([CH:21]=1)[C:8]([NH:10][CH2:11][C:12]1[CH:17]=[CH:16][CH:15]=[C:14]([N+:18]([O-:20])=[O:19])[CH:13]=1)=[O:9])#[N:2]Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- -78 °C
Procedure
To a stirring solution of (5-cyano-4-fluoro-2-methoxy-N-(3-nitro-benzyl)-benzamide (1.5 g, 4.6 mmol) in dichloromethane (200 mL, 0.3 M) at −78° C. was added BBr3 (21.5 mL, 21.4 mmol). The mixture was allowed to stir for 45 min at −78° C. and the dry ice/acetone bath was then removed and tje solution was allowed to warm to room temperature. Then, the solution was cooled down again to −78° C. and was then quenched with 100 mL of methanol. The mixture was allowed to warm to room temperature and concentrated. Purification by MPLC (10–100% ethyl acetate, 23 mL/min, 75 min) provided 5-cyano-4-fluoro-2-hydroxy-N-(3-nitro-benzyl)-benzamide (0.85 g, 59%) as a beige powder: Rf 0.37 (70% ethyl acetate in heptane); 1H NMR (DMSO-d6, 300 MHz) δ 9.50 (bd s, 1 H), 8.39 (d, J=7.5 Hz, 1 H;), 8.20 (s, 1 H), 8.12 (d, J=9.3 Hz, 1 H), 7.80 (d, J=7.2 Hz, 1H), 7.63 (t, J=7.8 Hz, 1 H), 7.04 (d, J=11.1 Hz, 1 H), 4.62 (s, 2H).
Workup
- customthe dry ice/acetone bath was then removed
- temperatureto warm to room temperature
- temperatureThen, the solution was cooled down again to −78° C.
- customwas then quenched with 100 mL of methanol
- temperatureto warm to room temperature
- concentrationconcentrated
- customPurification by MPLC (10–100% ethyl acetate, 23 mL/min, 75 min)
Sources & evidence
- ORD record
- ord-f24bcc99f2a142058ac1b1303108bbc4
- Source dataset
- uspto-grants-2007_03
- Patent number
- US07189749B2
Reaction notes
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