반응 #218271

반응 방정식

NaH

triethyl 2-phosphonopropionate

AcOH

isobutyric aldehyde

→

2,4-dimethylpent-2-enoic acid ethyl ester

수율 75.0%

용매

DME

dimethoxyethane

반응 조건

후처리

1. 1
   온도The mixture was then heated
2. 2
   온도to reflux
3. 3
   온도after 15 min. at reflux temp
4. 4
   온도at reflux
5. 5
   추출the product was extracted with Et2O (2×200 ml)
6. 6
   세척The combined organic extracts were washed with water (400 ml) and brine (100 ml)
7. 7
   건조dried (Na2SO4)
8. 8
   농축concentrated in a rotary evaporator
9. 9
   workup.DISTILLATIONThe resulting residue was distilled

실험 절차

Within a period of 90 min., a solution of triethyl 2-phosphonopropionate (238 g, 1.00 mol) in dimethoxyethane (DME, 150 ml) was added dropwise with stirring under an atmosphere of N2 to a solution of NaH (43.6 g, 1.00 mol) in DME (600 ml). The mixture was then heated to reflux, and after 15 min. at reflux temp., isobutyric aldehyde (72.1 g, 1.00 mol) was added dropwise. After a further 30 min. stirring at reflux, the mixture was poured into ice/water (1:1, 1 L). AcOH (60 ml) was added, and the product was extracted with Et2O (2×200 ml). The combined organic extracts were washed with water (400 ml) and brine (100 ml), dried (Na2SO4), and concentrated in a rotary evaporator. The resulting residue was distilled to provide at 86-75° C./27 mbar 117 g (75%) of 2,4-dimethylpent-2-enoic acid ethyl ester.

출처