Reacción #339440

ord-658789fe53894ce0bb445e0f1fc72f39

Condiciones de reacción

Temperatura
-70°CELSIUS
Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    TemperaturaThe yellow colored reaction mixture was slowly warmed to room temperature
  2. 2
    ConcentraciónThe reaction mixture was concentrated under reduced pressure
  3. 3
    Lavadothe residue washed with diethyl ether
  4. 4
    Otrodried
  5. 5
    Temperaturacooled
  6. 6
    Otroto 0° C.
  7. 7
    TemperaturaThe reaction mixture was slowly warmed to room temperature
  8. 8
    OtroSolvent was removed under reduced pressure
  9. 9
    Otrothe crude product was purified over silica gel (n-heptane/tert.butylmethyl ether 1:9 to 1:4 v/v)
  10. 10
    Otroto yield a white solid

Procedimiento

2-Methoxy-5-(3-methyl-thiophen-2-yl)-pyridine (0.32 g, 1.6 mmol) was dissolved in THF/diethyl ether (10 ml, 1:1 v/v) and cooled to −70° C. BuLi (1.6M hexanes, 1 ml, 1.6 ml) was added dropwise and after a further 15 min at −70° C. the reaction mixture was added via canula to a condensed solution of SO2 (5 ml) in diethyl ether (10 ml). The yellow colored reaction mixture was slowly warmed to room temperature and stirred overnight. The reaction mixture was concentrated under reduced pressure and the residue washed with diethyl ether and dried. The crude solid (0.31 g) was suspended in dry n-hexane (7 ml), cooled using an ice bath to 0° C. and treated with a solution of sulfuryl chloride (1 M, 1.2 ml, 1.2 mmol) in CH2Cl2. The reaction mixture was slowly warmed to room temperature and analyzed (TLC) showing no starting material. Solvent was removed under reduced pressure and the crude product was purified over silica gel (n-heptane/tert.butylmethyl ether 1:9 to 1:4 v/v) to yield a white solid: 0.19 g (38%), MS: m/e 304.0 (MH+).

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US07868030B2uspto-grants-2011_01