Hydrochloric Acid → Ethyl 6-bromobenzo[d]isoxazole-3-carboxylate

HRID 2261827Notes

Reaction equation

HRID 2261827 reaction equation
[CH3:1][O:2][C:3](=[O:15])[CH2:4][C:5]1[CH:10]=[CH:9][C:8]([Br:11])=[CH:7][C:6]=1[N+]([O-])=O.[N:16](OCCC(C)C)=[O:17].[CH3:24]C[O-].[Na+].Cl>C(O)C>[CH2:1]([O:2][C:3]([C:4]1[C:5]2[CH:10]=[CH:9][C:8]([Br:11])=[CH:7][C:6]=2[O:17][N:16]=1)=[O:15])[CH3:24]

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 8053Isoamyl NitriteHCID 2723922Sodium ethoxideHCID 15740598Methyl 4-bromo-2-nitrophenylacetate

Product 1

HCID 53401270Ethyl 6-bromobenzo[d]isoxazole-3-carboxylateYield 37%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent2×

Conditions

Temperature
60 °C

Procedure

A solution of (4-bromo-2-nitro-phenyl)-acetic acid methyl ester (0.99 g, 3.61 mmol) in ethanol (8 mL) at room temperature is treated with isoamyl nitrite (0.60 mL, 4.47 mmol). A solution of NaOEt in ethanol (1.9 M, 2.0 ml) is added, and the mixture is stirred at 60° C. for 2 hours and at room temperature for 16 hours. The mixture is neutralized with HCl (1.0 M, 4.0 mL) and concentrated. The residue is extracted with ethyl acetate (20 mL×2) and the combined organic layers are dried over sodium sulfate and concentrated. The residue is purified via silica gel chromatography eluting with 25% ethyl acetate in hexanes to give 6-bromo-benzo[d]isoxazole-3-carboxylic acid ethyl ester (0.36 g, 37%). ES/MS m/e 269.8; 271.8 (M+1).

Workup

  1. concentrationconcentrated
  2. extractionThe residue is extracted with ethyl acetate (20 mL×2)
  3. dry with materialthe combined organic layers are dried over sodium sulfate
  4. concentrationconcentrated
  5. customThe residue is purified via silica gel chromatography
  6. washeluting with 25% ethyl acetate in hexanes

Sources & evidence

ORD record
ord-4d33d4244d064779849d3dda2109b93c
Source dataset
uspto-grants-2010_12
Patent number
US07846960B2

Reaction notes

Loading…