Reaktion #74947

Reaktionsgleichung

hydrochloric acid

butyl-lithium

2-bromo-3,4-dimethylpyridine

furfural

sodium hydroxide

→

2-furyl-(3,4-dimethyl-2-pyridyl)-carbinol

Ausbeute 24.0%

Lösungsmittel

ether

ether

ether

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONOnce the addition
2. 2
   Temperaturmaintaining the same temperature
3. 3
   TemperaturThe temperature is increased to -25° C.
4. 4
   Temperaturis increased to -15° C.
5. 5
   workup.STIRRINGthe mixture is stirred for one hour
6. 6
   Temperaturcooling from the exterior with ice
7. 7
   Temperaturis cooled from the exterior and
8. 8
   Extraktionis extracted with ether
9. 9
   TrocknenThe ether layer is dried over anhydrous sodium sulphate
10. 10
    Filtrationfiltered
11. 11
    Sonstigeevaporated to dryness
12. 12
    Filtrationis purified by filtration through a silica gel column
13. 13
    Sonstigeare collected

Vorschrift

To 120 ml of a 0.74 M ether solution of butyl-lithium, there is slowly added under nitrogen atmosphere a solution of 10 g of 2-bromo-3,4-dimethylpyridine in 25 ml of anhydrous ether, the temperature being maintained at -40° C. Once the addition is concluded stirring is continued for one hour and 30 minutes, maintaining the same temperature. The temperature is increased to -25° C. and a solution of 5.3 ml of recently distilled furfural in 10 ml of anhydrous ether is added dropwise, following which the temperature is increased to -15° C. and the mixture is stirred for one hour. The reaction mixture is poured over 10% hydrochloric acid to acid pH, cooling from the exterior with ice. The aqueous layer is made alkaline with 10% sodium hydroxide, is cooled from the exterior and is extracted with ether. The ether layer is dried over anhydrous sodium sulphate, filtered and evaporated to dryness, the result being 4.9 g of an oil which is purified by filtration through a silica gel column. The fractions eluated with 95/5 and 70/30 proportions of benzene/chloroform, are collected to obtain 2.65 g (Yield 24%) of 2-furyl-(3,4-dimethyl-2-pyridyl)-carbinol (I). An analytical sample recrystallized from ethyl alcohol has a melting point of 61°-62° C. Calculated analysis for C12H13NO2 : C.70.91; H.6.45; N.6.89. Found: C.70.65; H.6.45; N. 6.88.

Quelle