N-bromobutanimide → Methyl 4-bromo-5-phenylisoxazole-3-carboxylate

HRID 1804476Notes

Reaction equation

HRID 1804476 reaction equation
[C:1]1([C:7]2[O:11][N:10]=[C:9]([C:12]([O:14][CH3:15])=[O:13])[CH:8]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[Br:16]N1C(=O)CCC1=O>[N+]([O-])(O)=O.C(O)(=O)C>[Br:16][C:8]1[C:9]([C:12]([O:14][CH3:15])=[O:13])=[N:10][O:11][C:7]=1[C:1]1[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

5

Reactant 2

HCID 67184N-bromobutanimideHCID 905953Methyl 5-phenyl-1,2-oxazole-3-carboxylate

Product 1

HCID 6426093Methyl 4-bromo-5-phenylisoxazole-3-carboxylateYield 77.8%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 944Nitric AcidSolvent

Procedure

A solution of methyl 5-phenylisoxazole-3-carboxylate (100 mg, 0.492 mmol) and N-bromosuccinimide (119 mg, 0.669 mmol) in 5% fuming nitric acid in acetic acid (2 mL) was heated to 150° C. for 10 minutes via microwave. The reaction mixture was concentrated and purified by silica gel chromatography with hexanes/ethyl acetate (10/1) to afford methyl 4-bromo-5-phenylisoxazole-3-carboxylate (108 mg). The compound had an HPLC ret. time=3.21 min.−Column: YMC S5 COMBISCREEN® 4.6×50 mm; Gradient time: 4 min; Flow rate=4 ml/min; Solvent A=10% MeOH−90% Water−0.2% H3PO4; Solvent B=90% MeOH−10% water−0.2% H3PO4; Start % B=0; Final % B=100. LC-MS: M+1=284+.

Workup

  1. concentrationThe reaction mixture was concentrated
  2. custompurified by silica gel chromatography with hexanes/ethyl acetate (10/1)

Sources & evidence

ORD record
ord-2910e66b19c8424a83e3571010ceb6ee
Source dataset
uspto-grants-2013_01
Patent number
US08354398B2

Reaction notes

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