Triethylamine → Ethyl 3-(3-methyl-4-nitrophenyl)isoxazole-5-carboxylate

HRID 75800Notes

Reaction equation

HRID 75800 reaction equation
[OH:1]/[N:2]=[C:3](\Cl)/[C:4]1[CH:9]=[CH:8][C:7]([N+:10]([O-:12])=[O:11])=[C:6]([CH3:13])[CH:5]=1.[C:15]([O:19][CH2:20][CH3:21])(=[O:18])[C:16]#[CH:17].CCN(CC)CC>C1(C)C=CC=CC=1.CCOC(C)=O.Cl>[CH3:13][C:6]1[CH:5]=[C:4]([C:3]2[CH:17]=[C:16]([C:15]([O:19][CH2:20][CH3:21])=[O:18])[O:1][N:2]=2)[CH:9]=[CH:8][C:7]=1[N+:10]([O-:12])=[O:11]

Participants

7

Reactant 3

HCID 8471TriethylamineHCID 12182Ethyl propiolateHCID 23159814(Z)-N-Hydroxy-3-methyl-4-nitrobenzene-1-carbonimidoyl chloride

Product 1

HCID 67352122Ethyl 3-(3-methyl-4-nitrophenyl)isoxazole-5-carboxylateYield 65%

Reagents, catalysts & solvents 3

HCID 313Hydrochloric AcidSolventHCID 1140TolueneSolventHCID 8857Ethyl AcetateSolvent

Procedure

To a solution of (Z)—N-hydroxy-3-methyl-4-nitrobenzimidoyl chloride (1.0 equiv.), ethyl propiolate (2.0 equiv.) in toluene was dropwise added Et3N over a period of 30 min. at RT and continued stirring at RT for 15 min. The reaction mixture was then heated at 80° C. for 16 hours. Reaction mass was diluted with EtOAc and neutralized with dilute HCl. The organic layer was washed with water, brine, dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography on silica gel, eluting with 100% CHCl3, to provide the title compound as creamish crystals (65%); 1H NMR (300 MHz, DMSO-d6) δ: 1.31-1.36 (t, J=7.0 Hz, 3H), 2.56 (s, 3H), 4.35-4.42 (q, 2H), 7.99-8.02 (m, 2H), 8.08 (s, 1H), 8.11 (m, 1H); IR (KBr) 3124, 3091, 2995, 2908, 1727, 1612, 1588, 1520, 1443, 1344, 1285, 1140, 1015, 950, 873, 771 cm−1.

Workup

  1. customof 30 min.
  2. customat RT
  3. temperatureThe reaction mixture was then heated at 80° C. for 16 hours
  4. customReaction mass
  5. washThe organic layer was washed with water, brine
  6. dry with materialdried over Na2SO4
  7. filtrationfiltered
  8. concentrationconcentrated in vacuo
  9. customThe residue was purified by flash chromatography on silica gel
  10. washeluting with 100% CHCl3

Sources & evidence

ORD record
ord-024128be01ee4d7291e37ab62f2cfc44
Source dataset
uspto-grants-2014_09
Patent number
US08835428B2

Reaction notes

Loading…