Reaktion #452229

Reaktionsgleichung

4-formylbenzoic acid methyl ester

phenylpropyl triphenylphosphonium bromide

→

4-(4-Phenyl-1-butenyl)benzoic acid, methyl ester

Lösungsmittel

THF

H2O

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto warm to room temperature
2. 2
   workup.STIRRINGThis solution was stirred for 3 hours at room temperature
3. 3
   Einengenconcentrated
4. 4
   Sonstigeto remove most of the THF
5. 5
   workup.ADDITIONEtOAc (~200 ml) was added
6. 6
   Waschenthe mixture was washed with H2O, 1N HCl (2×) and brine
7. 7
   TrocknenAfter drying over anhydrous MgSO4
8. 8
   Sonstigethe solvent was removed in vacuo
9. 9
   Sonstigeto yield a yellow oil which
10. 10
    SonstigeColumn purification of this crude product
11. 11
    Wascheneluted with 95:5 hexane/EtOAc
12. 12
    workup.ADDITIONProduct containing fractions
13. 13
    Sonstigeto yield
14. 14
    Einengenafter concentration title compound, 1.5 g (93%) as a clear oil

Vorschrift

To a 0° solution of phenylpropyl triphenylphosphonium bromide (3.55 g, 1.25 eq) in 30 ml of dry THF under argon was added K-t-amylate (3.9 ml, 1.1 eq). After stirring for 30 minutes at 0° C. then allowing to warm to room temperature, a solution of 4-formylbenzoic acid methyl ester (1.0 g, 6.1 mmol) in ~8 ml of dry THF was added dropwise. This solution was stirred for 3 hours at room temperature, then diluted with ~1 ml of H2O, and concentrated to remove most of the THF. EtOAc (~200 ml) was added and the mixture was washed with H2O, 1N HCl (2×) and brine. After drying over anhydrous MgSO4, the solvent was removed in vacuo to yield a yellow oil which solidified soon after. Column purification of this crude product was done on a 50 mm column on silica gel eluted with 95:5 hexane/EtOAc. Product containing fractions were combined to yield after concentration title compound, 1.5 g (93%) as a clear oil.

Quelle