Reacción #955937

Ecuación de reacción

EtMgBr

methyl 4-chloro-2-methoxybenzoate

→

methyl 4-ethyl-2-methoxybenzoate

Rendimiento 50.0%

Disolventes

THF

NMP

ether

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrogiving a red color
2. 2
   Otroquenched upon the addition of aq. HCl (1M, 50 mL)
3. 3
   ExtracciónThe crude product was extracted with ether
4. 4
   Lavadothe combined organic layers were successively washed with water and brine
5. 5
   Secadodried over MgSO4
6. 6
   Filtraciónfiltered
7. 7
   Otroevaporated
8. 8
   OtroThe residue was purified on silica gel (Eluent: 30% EtOAc in hexanes)

Procedimiento

To a solution of methyl 4-chloro-2-methoxybenzoate (example 18d) (4.16 g, 20.8 mmol) in THF (120 mL) and NMP (12 mL) was added under inert atmosphere Iron (III) acetylacetonate (398 mg, 1.17 mmol) giving a red color. Then EtMgBr (29 ml of 1M solution in ether) was added dropwise under vigorous stirring. The mixture turned dark brown and then violet and then was stirred for 15 more min. The reaction was diluted with ether and quenched upon the addition of aq. HCl (1M, 50 mL). The crude product was extracted with ether and the combined organic layers were successively washed with water and brine, dried over MgSO4, filtered and evaporated. The residue was purified on silica gel (Eluent: 30% EtOAc in hexanes) to give methyl 4-ethyl-2-methoxybenzoate (2.01 g, 50%) as an oil. 1H NMR (300 MHz, dMSO): δ 1.20-1.22(t, 3H), 2.65-2.7 (dd, 2H), 3.9 (s, 3H), 6.8 (s, 1H), 6.97 (m, 1H), 7.7 (m, 1H).

Fuente