Boron tribromide → HCID 135830957, compound

HRID 1824780Notes

Reaction equation

HRID 1824780 reaction equation
[Cl:1][C:2]1[C:7]2[N:8]=[C:9]([C:11]3[CH:16]=[CH:15][C:14]([OH:17])=[CH:13][CH:12]=3)[O:10][C:6]=2[CH:5]=[C:4]([O:18]C)[CH:3]=1.B(Br)(Br)Br>ClCCl>[Cl:1][C:2]1[C:7]2[N:8]=[C:9]([C:11]3[CH:12]=[CH:13][C:14]([OH:17])=[CH:15][CH:16]=3)[O:10][C:6]=2[CH:5]=[C:4]([OH:18])[CH:3]=1

Participants

4

Reactant 2

HCID 25134Boron tribromideHCID 135830950HCID 135830950, compound

Product 1

HCID 135830957HCID 135830957, compoundYield 23.3%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Conditions

Temperature
-78 °C

Procedure

To a suspension of 4-chloro-2-(4-hydroxyphenyl)-6-methoxybenzoxazole (240 mg) in dichloromethane (5 mL) cooled at −78° C. was added boron tribromide (5 mL, 1M solution in dichloromethane, 5.7 eq.). The mixture was stirred at −78° C. for 10 min, warmed to room temperature and stirred for 3 h. The mixture was poured onto ice/water and extracted with ethyl acetate. The organic layer was washed with brine and dried over MgSO4. Chromatography on a silica gel column (eluant: acetone-dichloromethane, gradient from 0:100 to 5:95) and trituration of the resulting solid in dichloromethane afforded the title compound (53 mg) as a solid. NMR (DMSO-d6): 10.31 (s, 1H), 10.17 (s, 1H), 7.98 (d, 2H, J=8.4 Hz), 7.06 (s, 1H), 6.95 (d, 2H, J=8.4 Hz), 6.87 (s, 1H); MS: 262 (MH+); HPLC tR: 1.99 min.

Workup

  1. temperaturewarmed to room temperature
  2. stirringstirred for 3 h
  3. additionThe mixture was poured onto ice/water
  4. extractionextracted with ethyl acetate
  5. washThe organic layer was washed with brine
  6. dry with materialdried over MgSO4

Sources & evidence

ORD record
ord-f53440a3cf0a43878be57a0c3c10a6f1
Source dataset
uspto-grants-2006_05
Patent number
US07045539B2

Reaction notes

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