Reaktion #52141

ord-33cdc04604e04380b23741afea793e55

Lösungsmittel

Reaktionsbedingungen

Temperatur
-78°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    workup.ADDITIONThe addition
  2. 2
    workup.WAITwas complete within 2 h
  3. 3
    Temperaturto warm to 0° C. within 2 h
  4. 4
    Sonstigequenched by addition of NH4Cl solution (200 ml)
  5. 5
    SonstigeThe organic layer was separated
  6. 6
    Waschenwashed with brine (250 ml)
  7. 7
    Trocknendried (Na2SO4)
  8. 8
    Filtrationfiltered
  9. 9
    Sonstigeevaporated
  10. 10
    SonstigeThe solid was recrystallized from methanol

Vorschrift

To a solution of 3,4,5-trimethoxybromobenzene 18 (62.3 g, 0.25 mol) in dry THF (200 ml) was added BuLi solution (169 ml, 1.6M in hexane, 0.27 mol) dropwise at −78° C. within 45 min. The resulting beige-colored suspension was stirred for an additional 1 h at −78° C. Then PPh2Cl (61 g, 0.277 mol. 49.7 ml) was added dropwise. The addition was complete within 2 h. The resulting yellow solution was allowed to warm to 0° C. within 2 h and quenched by addition of NH4Cl solution (200 ml). The organic layer was separated, washed with brine (250 ml), dried (Na2SO4), filtered, and evaporated. The solid was recrystallized from methanol to give 69.5 g (80%) of 19.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US06855657B2uspto-grants-2005_02