반응 #585327

반응 방정식

5-bromo-2-methyl-2-pentene

magnesium

5-(2-phenyl-1,3-dioxolan-2-yl)-2-pentanone

NH4Cl

→

yellow oil

수율 38.0%

4,8-dimethyl-1-(2-phenyl-1, 3-dioxolan-2-yl)-7-nonen-4-ol

수율 38.0%

용매

ether

ether

ether

heptane ether

반응 조건

후처리

1. 1
   workup.WAITDuring the introduction, the temperature was left
2. 2
   기타rising up to −5° C.
3. 3
   workup.WAITthe reaction mixture left
4. 4
   추출Extraction with ether (2×)
5. 5
   세척washing with water (3×)
6. 6
   건조drying (Na2SO4)
7. 7
   농축concentrating
8. 8
   기타gave 6.24 g of the crude product

실험 절차

A Grignard reagent of 3.50 g (0.021 mol) of 5-bromo-2-methyl-2-pentene in 13 ml of ether and 0.62 g (0.026 mol) of magnesium turnings in 14 ml of ether was added slowly at −25° under N2 to a stirred solution of 5.54 g (0.024 mol) of 5-(2-phenyl-1,3-dioxolan-2-yl)-2-pentanone obtained under b) in 20 ml of ether. During the introduction, the temperature was left rising up to −5° C. and the reaction mixture left stirring for 45 min. Then a saturated solution of NH4Cl was added and the formation of a white precipitate was observed. Extraction with ether (2×), washing with water (3×), drying (Na2SO4) and concentrating gave 6.24 g of the crude product. Column chromatography (SiO2, heptane/ether 7:3) gave 2.53 g (38%) of a yellow oil.

출처