Reaktion #61198

ord-6174ef22ddd04e3fb1dba4dc7efa5329

Lösungsmittel

Reaktionsbedingungen

Temperatur
-40°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Temperaturcooled to −78° C.
  2. 2
    Sonstigeto attain RT
  3. 3
    workup.STIRRINGstirred for 1 h
  4. 4
    SonstigeThe reaction was quenched with satd aq NH4Cl
  5. 5
    workup.ADDITIONdiluted with EtOAc (20 mL)
  6. 6
    Waschenwashed with brine (2×20 mL)
  7. 7
    Trocknenthe organic layer was dried over Na2SO4
  8. 8
    Einengenconcentrated
  9. 9
    WaschenThe title compound was eluted from a 20-g SPE cartridge (silica) with 30% EtOAc/hexane

Vorschrift

To a solution of 2-bromo-1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazole-4-carbonitrile (0.55 g, 1.8 mmol) (as prepared in the previous step) in THF (6 mL) at −40° C. was added dropwise a solution of 2M i-PrMgCl in THF (1 mL). The reaction was allowed to stir for 10 min at −40° C. and then cooled to −78° C., and ethyl cyanoformate (0.3 g, 3.0 mmol) was added. The reaction allowed to attain RT and stirred for 1 h. The reaction was quenched with satd aq NH4Cl, diluted with EtOAc (20 mL) and washed with brine (2×20 mL), and the organic layer was dried over Na2SO4 and then concentrated. The title compound was eluted from a 20-g SPE cartridge (silica) with 30% EtOAc/hexane to give 0.40 g (74%) of a colorless oil. Mass spectrum (ESI, m/z): Calcd. for C13H21N3O3Si, 296.1 (M+H), found 296.1.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US07427683B2uspto-grants-2008_09