Reaktion #51198

Reaktionsgleichung

Diethyl-cyanomethyl phosphonate

NaH

4-bromobenzaldehyde

→

3-(4-Bromophenyl)-2-propenenitrile

Lösungsmittel

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto warm to room temperature overnight
2. 2
   SonstigeThe reaction was quenched with water
3. 3
   Extraktionextracted with EtOAc (3×50 ml)
4. 4
   Trocknendried (MgSO4)
5. 5
   Filtrationfiltered
6. 6
   Sonstigeevaporated to a yellow oil
7. 7
   workup.ADDITIONThis oil was taken up in a 9:1 mixture of pentane
8. 8
   SonstigeEtOAc from which the title product crystallised (5.8 g, 52%)

Vorschrift

A 60% suspension of NaH in mineral oil (2.16 g, 54.1 mmol) was suspended in THF (50 ml) and cooled to 0° C. under nitrogen. Diethyl-cyanomethyl phosphonate (8.74 ml, 54.1 mmol) was added dropwise and the whole stirred at 0° C. for 30 min. 4-bromobenzaldehyde (10 g, 54.1 mmol) was then added dropwise as a solution in 20 ml THF, and the mixture allowed to warm to room temperature overnight. The reaction was quenched with water, extracted with EtOAc (3×50 ml), dried (MgSO4) and then filtered and evaporated to a yellow oil. This oil was taken up in a 9:1 mixture of pentane:EtOAc from which the title product crystallised (5.8 g, 52%); 1HNMR (400 MHz, CDCl3) δ: 5.82 (d, 1H), 7.21-7.28 (m, 3H), 7.50 (d, 2H).

Quelle