Reacción #51609

Ecuación de reacción

sodium methoxide

1-[2-hydroxy-3-methyl-4-(phenylmethoxy)phenyl]-ethanone

ethanedioic acid, diethyl ester

→

8-methyl-4-oxo-7-(phenylmethoxy)-4H-1-benzopyran-2-carboxylic acid

Rendimiento 95.4%

Disolventes

toluene

toluene

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturarefluxed for 2 hours
2. 2
   OtroThe solvent was evaporated
3. 3
   workup.ADDITIONThe residue was added to a mixture of acetic acid (150 ml) and hydrochloric acid (50 ml)
4. 4
   workup.STIRRINGThe reaction mixture was stirred
5. 5
   Temperaturarefluxed for 1 hour
6. 6
   workup.ADDITIONThe mixture was poured out onto ice
7. 7
   FiltraciónThe resulting precipitate was filtered off
8. 8
   Otrodried (vacuum; 70° C.)

Procedimiento

A mixture of 1-[2-hydroxy-3-methyl-4-(phenylmethoxy)phenyl]-ethanone (0.098 mol) and ethanedioic acid, diethyl ester (0.11 mol) in toluene (100 ml) was added dropwise to a mixture of sodium methoxide (0.22 mol) in toluene (150 ml). The reaction mixture was stirred and refluxed for 2 hours. The solvent was evaporated. The residue was added to a mixture of acetic acid (150 ml) and hydrochloric acid (50 ml). The reaction mixture was stirred and refluxed for 1 hour. The mixture was poured out onto ice. The resulting precipitate was filtered off and dried (vacuum; 70° C.), yielding 29 g (95.4%) of 8-methyl-4-oxo-7-(phenylmethoxy)-4H-1-benzopyran-2-carboxylic acid (interm. 9).

Fuente