Reacción #1778

ord-c76a22e184294ef893b6fc5df9e611d7

Ecuación de reacción

OC1CCOc2ccccc21
4-chromanol
CCOC(=O)N=NC(=O)OCC
diethyl azodicarboxylate
COC(=O)c1ccc(O)cc1OC
methyl 4-hydroxy-2-methoxybenzoate
c1ccc(P(c2ccccc2)c2ccccc2)cc1
triphenylphosphine
COC(=O)c1ccc(OC(=O)C2CCOc3ccccc32)cc1OC
methyl 4-(4-chromanoyloxy)-2-methoxybenzoate

Disolventes

Condiciones de reacción

Temperatura
0°CELSIUS
Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    FiltraciónThe reaction was filtered
  2. 2
    Otrothe solvent was removed under reduced pressure
  3. 3
    OtroThe residue was chromatographed on a silica gel column
  4. 4
    LavadoEtOAc and eluted with same
  5. 5
    Otrothe solvent removed under reduced pressure

Procedimiento

To a stirred solution of methyl 4-hydroxy-2-methoxybenzoate (364 mg, 2.0 mmol) in dry THF (1.25 mL) was added triphenylphosphine (525 mg, 2.0 mmol) and the solution was cooled to 0° C. A 500 mL volume of 4-chromanol (200 mg, 1.33 mmol) and diethyl azodicarboxylate (315 mL, 2.0 mmol) in THF was added dropwise via syringe over 0.5 h. The reaction was filtered and the solvent was removed under reduced pressure. The residue was chromatographed on a silica gel column packed in 92:8 hexanes:EtOAc and eluted with same. The appropriate fractions were combined and the solvent removed under reduced pressure to afford methyl 4-(4-chromanoyloxy)-2-methoxybenzoate.

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US05726172uspto-grants-1998_03