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

HRID 250257Notes

Reaction equation

HRID 250257 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 under reduced pressure. The residue is extracted with ethyl acetate (20 mL×2) and the combined organic layers are dried over sodium sulfate and concentrated under reduced pressure. The residue is purified via silica gel chromatography eluting with 25% ethyl acetate in hexanes to give the title compound (0.36 g, 37%). ES/MS m/e 269.8; 271.8 (M+1).

Workup

  1. concentrationconcentrated under reduced pressure
  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 under reduced pressure
  5. customThe residue is purified via silica gel chromatography
  6. washeluting with 25% ethyl acetate in hexanes

Sources & evidence

ORD record
ord-05d42b6009a843f4b5ea5ee94dad3801
Source dataset
uspto-grants-2011_01
Patent number
US07863302B2

Reaction notes

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