Reacción #2006484

ord-72194fa333434a04aefac894f5a0ea8f

Condiciones de reacción

Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    Otroto return to room temperature
  2. 2
    Filtraciónfiltered on a cotton plug
  3. 3
    OtroPurification of the resulting crude product by flash chromatography

Procedimiento

To a solution of compound 20a (33 mg, 0.097 mmol) in anhydrous dichloromethane (2 mL) at 0° C. under argon were added triphenylphosphine (50 mg, 0.194 mmol) and carbontetrabromide (64 mg, 0.194 mmol). The solution was allowed to return to room temperature and stirred for 1 hr. The resulting solution was diluted with dichloromethane (25 mL) and filtered on a cotton plug. Purification of the resulting crude product by flash chromatography using a gradient of ethyl acetate/hexane (3:97 to 3:7) as an eluant gave the desired compound 21a (15 mg, 40% for 2 steps). 1H NMR (400 MHz, Acetone-d6) δ: 1.36 (s, 3H), 1.39 (s, 3H), 1.40 (s, 3H), 2.28 (m, 2H), 3.68 (m, 2H), 8.03 (dd, 1H, J1=6.57 Hz, J2=1.84 Hz), 8.14 (d, 1H, J=1.45 Hz), 8.24 (d, 1H, J=8.40 Hz).

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US08168627B2uspto-grants-2012_05