Reacción #162976

Ecuación de reacción

3-fluoro-4-nitro-benzaldehyde oxime

hydroxy tosyloxy iodobenzene

ethyl propiolate

→

title compound

Rendimiento 74.0%

3-(3-Fluoro-4-nitro-phenyl)-isoxazole-5-carboxylic acid ethyl ester

Rendimiento 74.0%

Disolventes

acetonitrile

ethyl acetate

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe resulting reaction mixture
2. 2
   workup.STIRRINGwas stirred at 80° C. for 2-3 h
3. 3
   OtroAfter the completion of the reaction, it
4. 4
   Otrowas evaporated to dryness
5. 5
   OtroThe solid thus obtained
6. 6
   Lavadowashed with brine
7. 7
   Secadodried over anhydrous Na2SO4
8. 8
   OtroThe solvent was removed
9. 9
   Otrothe residue was purified by flash chromatography over silica gel with 20% ethyl acetate in light petroleum

Procedimiento

To a solution of 3-fluoro-4-nitro-benzaldehyde oxime (6 g; 32.6 mmol) in acetonitrile (120 mL) was added hydroxy tosyloxy iodobenzene (16.58 g; 42.3 mmol) and ethyl propiolate (6.38 g; 65.2 mmol) under stirring. The resulting reaction mixture was stirred at 80° C. for 2-3 h. After the completion of the reaction, it was evaporated to dryness. The solid thus obtained was dissolved in ethyl acetate and washed with brine and dried over anhydrous Na2SO4. The solvent was removed and the residue was purified by flash chromatography over silica gel with 20% ethyl acetate in light petroleum to give 6.4 g (74%) of the title compound. IR (KBr): 3134, 3060, 2975, 1717, 1610, 1593, 1522, 1458, 1446 cm−1; MS (m/z): 279 (M−−1); 1H NMR (DMSO-d6) δ: 1.31-136 (t, 3H, CH2CH3), 4.36-4.43 (q, 2H, CH2CH3), 8.04 (d, 1H, J=9.0, 6′-H), 8.09 (s, 1H, 4-H), 8.16 (d, 1H), 8.30 (t, 1H).

Fuente