Reaktion #5149

Reaktionsgleichung

(4-carbomethoxy)benzyltriphenylphosphonium bromide

methyl 4-formylbenzoate

sodium methoxide

toluene

→

4,4'-bis(carbomethoxy)stilbene

Ausbeute 79.3%

Lösungsmittel

methanol

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeTo a 2 L 3-neck round bottom flask fitted with a glass stopper, rubber septum
2. 2
   Temperaturreflux condenser with a nitrogen inlet tube
3. 3
   workup.DISSOLUTIONAfter the starting material dissolved
4. 4
   TemperaturThe reaction vessel was heated
5. 5
   Temperaturat reflux for 30 minutes
6. 6
   Temperaturthe reaction vessel was cooled at 0° C. for several hours
7. 7
   FiltrationThe resulting precipitate was filtered
8. 8
   Sonstigedried in a vacuum oven

Vorschrift

To a 2 L 3-neck round bottom flask fitted with a glass stopper, rubber septum, and reflux condenser with a nitrogen inlet tube, was added 126.35 g (251 mmol) (4-carbomethoxy)benzyltriphenylphosphonium bromide, 49.45 g (302 mmol) methyl 4-formylbenzoate, and 632 mL 2:1 methanol:toluene. After the starting material dissolved, 63.2 mL (277 mmol) 25% sodium methoxide solution in methanol was added dropwise over several minutes. The reaction vessel was heated at reflux for 30 minutes. After cooling to room temperature, the reaction vessel was cooled at 0° C. for several hours. The resulting precipitate was filtered and dried in a vacuum oven to afford 59.0 g (79%) 4,4'-bis(carbomethoxy)stilbene as a 7:3 mixture of cis:trans isomers.

Quelle