Reacción #1994220

Ecuación de reacción

calcium hydroxide

2,4-dimethylbenzoic acid

sulfuric acid

ethanol

→

1

Rendimiento 95.0%

Ethyl 2,4-Dimethylbenzoate

Rendimiento 95.0%

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe mixture was refluxed over night
2. 2
   Temperaturacooled down
3. 3
   FiltraciónThe suspension was filtered over celite and
4. 4
   Concentraciónconcentrated in vacuo
5. 5
   workup.DISTILLATIONThe crude product was purified by vacuum distillation

Procedimiento

To a solution of commercially available 2,4-dimethylbenzoic acid (67.8 g, 451 mmol) in 1000 mL of ethanol was added 10 mL of sulfuric acid. The mixture was refluxed over night, cooled down and was neutralized by adding calcium hydroxide in small portions (˜30 g). The suspension was filtered over celite and concentrated in vacuo. The crude product was purified by vacuum distillation yielding 76.4 g (95%) of 1 as a colorless oil: 1H-NMR (400 MHz, CDCl3): δ 1.38 (t, J=7.3 Hz, 3H), 2.34 (s, 3H), 2.57 (s, 3H), 4.33 (q, J=7.2 Hz, 2H), 7.01-7.06 (m, 2H), 7.82 (d, J=8.5 Hz, 1H); 13C-NMR (100 MHz, CDCl3): δ 14.3, 21.3, 21.7, 60.4, 126.3, 126.9, 130.7, 132.4, 140.1, 142.3, 167.6; MS (ESI) m/z=133.0 (100), 132.0 (57), 178.1 (M+, 51).

Fuente