Reacción #475925

ord-c8d96539bf9f41a083f36984ebc393c9

Condiciones de reacción

Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    Otrothe resulting layers were separated
  2. 2
    ExtracciónThe aqueous layer was extracted three times with 120 mL each of tert-butyl methyl ether
  3. 3
    Lavadowashed twice with 125 mL each of 10% aqueous NaCl
  4. 4
    SecadoThe tert-butyl methyl ether solution was dried over MgSO4
  5. 5
    Filtraciónthen filtered
  6. 6
    Concentraciónconcentrated in vacuo
  7. 7
    OtroThe product was purified on 2.00 kg of Silica Gel 60 with a gradient of hexanes

Procedimiento

The compound of Example 16A (11.0 g, 65 mmol) in 66 mL of dimethylformamide was treated with 5.37 g (1.2 equivalents) of imidazole followed by 11.2 g (1.14 equivalents) of tert-butyldimethylsilyl chloride. The reaction was stirred for 20 hours at ambient temperature. The reaction solution was mixed with 200 mL of water and the resulting layers were separated. The aqueous layer was extracted three times with 120 mL each of tert-butyl methyl ether. The organic layers were combined, and washed twice with 125 mL each of 10% aqueous NaCl. The tert-butyl methyl ether solution was dried over MgSO4 then filtered and concentrated in vacuo. The product was purified on 2.00 kg of Silica Gel 60 with a gradient of hexanes:tert-butyl methyl ether from 19:1 (8 L) to 9:1 (4 L) to afford 16.2 the titled compound (16.2 g, 91 %).

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US08377913B2uspto-grants-2013_02