Reacción #68812

Ecuación de reacción

tert-Butyl bromoacetate

4-hydroxybenzaldehyde

K2CO3

NaI

→

solid

Rendimiento 92.3%

4-(tert-Butoxycarbonylmethoxy)benzaldehyde

Rendimiento 92.3%

Disolventes

CH2Cl2

Water

acetonitrile

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   Otrothe phases were separated
3. 3
   ExtracciónThe aqueous layer was extracted with CH2Cl2
4. 4
   LavadoThe combined organic phase was washed with water
5. 5
   SecadoThe organic layer was dried (Na2SO4)
6. 6
   OtroEvaporation of the solvent and chromatography of the oily residue [silica, ethyl acetate/hexanes (3:7)]

Procedimiento

A solution of 4-hydroxybenzaldehyde (2.44 g, 20.0 mmol) in dry acetonitrile (8.0 mL) was treated with powdered, dried K2CO3 (3.04 g, 22.0 mmol) and NaI (304 mg, 2.00 mmol). The mixture was refluxed under argon for 30 min. tert-Butyl bromoacetate (1.48 mL, 1.95 g, 10.0 mmol) was added dropwise, and the reflux was continued for 12 h. Water and CH2Cl2 were added and the phases were separated. The aqueous layer was extracted with CH2Cl2. The combined organic phase was washed with water. The organic layer was dried (Na2SO4). Evaporation of the solvent and chromatography of the oily residue [silica, ethyl acetate/hexanes (3:7)] afforded a white, crystalline solid (2.18 g, 92%): mp 56-57° C.; IR (film, νmax cm−1) 1762, 1752, 1685, 1600; 1H NMR δ 1.48 (s, 9H), 4.60 (s, 2H), 6.99 (d, J=8.7 Hz, 2H), 7.84 (d, J=8.7 Hz, 2H), 9.89 (s, 1H); 13C NMR δ 28.25, 65.76, 83.17, 115.08, 130.82, 132.18, 163.00, 167.37, 190.98; EI-MS 105/107, 135, 193/194, 236/237; FAB-MS obsd 237.1120, calcd 237.1127 [(M+H)+, M=C13H16O4]; Anal. Calcd C, 66.09; H, 6.83. Found C, 66.06; H, 6.82.

Fuente