Reacción #69454

Ecuación de reacción

HCl

methyl 3-bromo-4-hydroxybenzoate

triethylamine

1-(vinyloxy)butane

→

methyl 3-acetyl-4-hydroxybenzoate

Rendimiento 82.0%

Disolventes

ether

DCM

ethanol

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe reaction was cooled down
2. 2
   Filtraciónfiltered
3. 3
   Concentraciónthe filtrate concentrated
4. 4
   workup.ADDITIONwas added
5. 5
   workup.STIRRINGStirring
6. 6
   Temperaturawas maintained for 2 h
7. 7
   Otrothe organic phase was separated
8. 8
   Secadodried over MgSO4
9. 9
   Filtraciónfiltered
10. 10
    Concentraciónconcentrated
11. 11
    Otroto afford a solid which
12. 12
    FiltraciónThe solid was filtered off
13. 13
    Concentraciónthe filtrate concentrated to dryness

Procedimiento

To a degassed solution of methyl 3-bromo-4-hydroxybenzoate (350 g, 1514.87 mmol) in ethanol (3 L) were added triethylamine (0.528 L, 3787.17 mmol), 1-(vinyloxy)butane (0.588 L, 4544.60 mmol), 1,1′-bis(diphenylphosphino)ferrocene (33.1 g, 60.6 mmol) and diacetoxypalladium (8.50 g, 37.9 mmol) under nitrogen. The mixture was heated at 70° C. overnight. The reaction was cooled down, filtered and the filtrate concentrated. The resulting solid was solubilized with DCM (2 L) and HCl 4N (1.14 L, 4544 mmol) was added under stirring. Stirring was maintained for 2 h, the organic phase was separated, dried over MgSO4, filtered and concentrated to afford a solid which was stirred in ether (5 L) for 2 h. The solid was filtered off and the filtrate concentrated to dryness to afford methyl 3-acetyl-4-hydroxybenzoate (240 g, 82%) as a beige powder. Mass spectrum: m/z [M−H]−=193.

Fuente