Reaktion #341717

Reaktionsgleichung

butyl-[1-(2,6-difluoro-phenyl)-meth-(E)-ylidene]-amine

ether

cyclopropylmagnesium bromide

diethyl ether

cyclopropylmagnesium bromide

cyclopropyl bromide

magnesium

diethyl ether

→

title compound

Ausbeute 64.0%

2,6-Dicyclopropyl-benzaldehyde

Ausbeute 64.0%

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThis compound was prepared
2. 2
   Sonstigedescribed in Synthesis 1999, 2138-2144
3. 3
   Temperaturby heating
4. 4
   Temperaturat reflux for 5 min
5. 5
   workup.ADDITIONAfter the addition
6. 6
   Temperaturfor 90 minutes at reflux
7. 7
   TemperaturThe reaction mixture was then cooled to room temperature
8. 8
   Sonstigequenched by dropwise addition of water
9. 9
   workup.ADDITIONbefore being diluted with ethyl acetate
10. 10
    WaschenThe mixture was then washed with saturated brine
11. 11
    SonstigeThe phases were separated
12. 12
    Trocknenthe organic phase was dried over Na2SO4
13. 13
    Filtrationfiltered
14. 14
    Einengenconcentrated in vacuo
15. 15
    SonstigeThe residue was purified by flash chromatography (silica gel, toluene/heptane gradient)

Vorschrift

This compound was prepared using methodology described in Synthesis 1999, 2138-2144. A solution of cyclopropylmagnesium bromide was first prepared by dropwise addition of a solution of 4.06 ml (50.7 mmol) cyclopropyl bromide in 20 ml diethyl ether to 1.23 g (50.7 mmol) magnesium turnings followed by heating at reflux for 5 min. Meanwhile, to a solution of 2.50 g (12.7 mmol) butyl-[1-(2,6-difluoro-phenyl)-meth-(E)-ylidene]-amine in 15 ml ether at 0° C. was added 0.16 g (1.27 mmol) manganese(II) chloride. The freshly prepared solution of cyclopropylmagnesium bromide in diethyl ether was then added dropwise while the temperature of the reaction mixture was maintained at 5-10° C. After the addition was complete, the reaction mixture was stirred for 30 minutes at room temperature and then for 90 minutes at reflux. The reaction mixture was then cooled to room temperature and quenched by dropwise addition of water before being diluted with ethyl acetate. The mixture was then washed with saturated brine. The phases were separated and the organic phase was dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography (silica gel, toluene/heptane gradient) to afford 1.51 g (64%) of the title compound as a yellow oil. MS (EI): 158.1 ([M-CO]+, 100%).157.1 ([M-CHO]+., 25%), 129.2 ([M-CHO—C2H4]+., 90%), 115.1 ([M-CHO—C3H6]+., 43%).

Quelle