Reacción #50921

ord-cde684b0dfb44ff4867ced69a2c281fc

Condiciones de reacción

Temperatura
-15°CELSIUS
Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    TemperaturaAfter cooling again to −70° C.
  2. 2
    workup.STIRRINGstirring
  3. 3
    workup.WAITwas continued for 1 h
  4. 4
    TemperaturaThe suspension was warmed to −60° C.
  5. 5
    Otrothe organic layer was separated
  6. 6
    ExtracciónThe aqueous layer was extracted three times with 750-ml portions of tert-butyl methyl ether
  7. 7
    Secadothe combined organic layers were dried (sodium sulfate)
  8. 8
    Otroevaporated

Procedimiento

Under argon) a solution of 75 g (268 mmol) 2,2-dimethyl-N-(6-thiomorpholin-4-yl-pyridin-3-yl)-propionamide, 187 g (1.61 mol) N,N,N′,N′-tetramethylethylenediamine and 85 g (604 mmol) 2,2,6,6,-tetramethylpiperidine in 750 ml tetrahydrofuran was cooled to −65° C. in a dry ice bath. Within 30 min, 805 ml (1.29 mol) of a 1.6 N n-butyllithium solution in hexane were added dropwise. The reaction mixture was allowed to warm up to −15° C. and was stirred for 3 h at this temperature. After cooling again to −70° C., 354 g (1.40 mol) iodine (dissolved in 1000 ml tetrahydrofuran) were added dropwise during 2 h and stirring was continued for 1 h. The suspension was warmed to −60° C. and was poured into 1000 ml of 30% sodium thiosulfate pentahydrate solution. Then, 750 ml tert-butyl methyl ether were added and the organic layer was separated. The aqueous layer was extracted three times with 750-ml portions of tert-butyl methyl ether and the combined organic layers were dried (sodium sulfate) and evaporated. Flash chromatography gave 68.9 g (63%) of the title compound as light brown crystals.

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US06849624B2uspto-grants-2005_02