Reacción #44923

Ecuación de reacción

Water

ethyl 3-methyl-4-oxocrotonate

ethyl [2-(2-isobutoxy-5-methoxyphenyl)-2-oxoethyl]-phosphonate

potassium tert-butoxide

→

ethyl 6-(2-isobutoxy-5-methoxyphenyl)-6-oxo-3-methylhexa-2,4-dienoate

Disolventes

tetrahydrofuran

tetrahydrofuran

tetrahydrofuran

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaHeating
2. 2
   Temperaturathe mixture is then cooled to 0° C.
3. 3
   workup.ADDITIONare added dropwise
4. 4
   Extracciónthe resulting mixture is extracted with ether
5. 5
   SecadoAfter drying (Na2SO4)
6. 6
   Otrothe solvent is evaporated off
7. 7
   Otrothe residue is purified by flash chromatography (dichloromethane) (2.58 g of yellow oil; 89%)

Procedimiento

3 g (8.4 mmol) of ethyl [2-(2-isobutoxy-5-methoxyphenyl)-2-oxoethyl]-phosphonate dissolved in 20 ml of tetrahydrofuran are added dropwise to a suspension of 1.41 g (12.6 mmol) of potassium tert-butoxide in 30 ml of tetrahydrofuran, heated to 50° C. Heating is continued for 20 minutes at 50° C., the mixture is then cooled to 0° C. and 1.8 g (12.6 mmol) of ethyl 3-methyl-4-oxocrotonate dissolved in 20 ml of tetrahydrofuran are added dropwise. The reaction mixture is then stirred for 72 hours at 25° C. Water is added and the resulting mixture is extracted with ether. After drying (Na2SO4), the solvent is evaporated off and the residue is purified by flash chromatography (dichloromethane) (2.58 g of yellow oil; 89%).

Fuente