Reacción #3211

Ecuación de reacción

methyl 2-amino-6-methoxybenzoate

dimethyl acetylenedicarboxylate

potassium t-butoxide

→

desired compound

Rendimiento 65.0%

Dimethyl 4-hydroxy-5-methoxyquinoline-2,3-dicarboxylate

Rendimiento 65.0%

Disolventes

t-butanol

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturathe resulting mixture was heated to 90° C. for 1.5 hr during which solids
2. 2
   Otroprecipitated out of solution
3. 3
   TemperaturaThe mixture was cooled to room temperature
4. 4
   Filtraciónfiltered
5. 5
   workup.DISSOLUTIONthe collected solids were dissolved in water
6. 6
   Otroto form a light tan precipitate
7. 7
   OtroThe solids were collected
8. 8
   Filtraciónfiltered
9. 9
   Lavadowashed with water and air
10. 10
    Otrodried

Procedimiento

A solution of methyl 2-amino-6-methoxybenzoate ((1.30 g, 7.17 mM) and dimethyl acetylenedicarboxylate (1.17 g, 8.23 mM) in t-butanol (11 mL) was refluxed under a nitrogen atmosphere for 4 hr. The reaction mixture was cooled to room temperature, potassium t-butoxide (0.92 g, 8.23 mM) was added, and the resulting mixture was heated to 90° C. for 1.5 hr during which solids precipitated out of solution. The mixture was cooled to room temperature, filtered and the collected solids were dissolved in water. The resulting solution was acidified with 1N H2SO4 to form a light tan precipitate. The solids were collected, filtered, washed with water and air dried to provide the desired compound (1.35 g, 65%) as a tan solid. A 0.28 g portion of this material was recrystallized from ethyl acetate to provide an analytical sample (0.24 g) of the title compound as a white solid, mp 184°-186° C.; MS(CI): 292 (M+H).

Fuente