Reaktion #540782

Reaktionsgleichung

Indium

2,2-dimethoxyacetaldehyde

allyl bromide

→

crude product

2-hydroxy-1,1-dimethoxypent-4-ene

Lösungsmittel

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe supernatant was decanted
2. 2
   Waschenwashed 3 times with ethanol (3×150 mL)
3. 3
   FiltrationThe combined supernatants were filtered
4. 4
   Sonstigeevaporated at reduced pressure
5. 5
   Sonstigeto provide a thick oil (45° C., clear yellow oil, 56 g)

Vorschrift

Indium powder (0.17 mol, 0.75 eq., 20 g, 100 mesh) was added to an ethanol (200 mL) solution containing 2,2-dimethoxyacetaldehyde (0.23 mol, 1.0 eq., 35 mL, 60 wt % solution in water) and allyl bromide (0.28 mol, 1.2 eq., 24 mL). The suspension was stirred at 40° C. for 3 h. The slurry was then centrifuged and the supernatant was decanted. The residual pellet was suspended in and washed 3 times with ethanol (3×150 mL). The combined supernatants were filtered and evaporated at reduced pressure to provide a thick oil (45° C., clear yellow oil, 56 g). The crude product resulting (25 g) was extracted with brine and ethyl acetate (2×). The combined organic layers were dried over sodium sulfate, filtered and evaporated at reduced pressure. Yield was 11 g (89%) of semi-purified oil. The product was purified by silica chromatography with a hexanes/ethyl acetate gradient on a Biotage SP-4 (FLASH 40+M) purification system. Purified yield 5.2 g (42%) clear colorless oil.

Quelle