Reaktion #987156

Reaktionsgleichung

acetonitrile

sodium hydride

5,5-dimethyl-3-(4-trifluoromethoxyphenyl)imidazolidine-2,4-dione

2-chloro-4-(bromomethyl)pyridine

→

5,5-dimethyl-1-(2-chloropyrid-4-ylmethyl)-3-(4-trifluoromethoxyphenyl)imidazolidine-2,4-dione

Ausbeute 69.7%

Lösungsmittel

dimethylformamide

water

dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONfollowed by addition of ice-cold water
2. 2
   Sonstigeafter reaction for 10 minutes
3. 3
   WaschenThe elution
4. 4
   workup.ADDITIONThe fractions containing the expected product
5. 5
   Einengenare concentrated under reduced pressure
6. 6
   Sonstige0.130 g of crude product is thus obtained
7. 7
   Sonstigewhich product is purified by a double chromatography
8. 8
   Wascheneluted with a mixture (cyclohexane/ethyl acetate), (8/2) (v/v) at a flow rate of 5 ml/minute
9. 9
   EinengenThe fractions between 30 and 75 ml are concentrated under reduced pressure

Vorschrift

0.028 g of sodium hydride is added to a solution of 0.1 g of 5,5-dimethyl-3-(4-trifluoromethoxyphenyl)imidazolidine-2,4-dione in 2 ml of anhydrous dimethylformamide, under an inert atmosphere of argon at a temperature in the region of 20° C. Stirring is continued at this temperature for 30 minutes. A solution of 0.1 g of 2-chloro-4-(bromomethyl)pyridine in 2 ml of dimethylformamide is added, followed by addition of ice-cold water after reaction for 10 minutes. The reaction medium is placed on a cartridge 20 mm in diameter packed with 17 g of octadecyl-grafted 50 μm silica conditioned successively with acetonitrile and then with water. The elution is performed by gradient using the mixture (water/acetonitrile) of from 0 to 100% acetonitrile. The fractions containing the expected product are concentrated under reduced pressure. 0.130 g of crude product is thus obtained, which product is purified by a double chromatography using a cartridge packed with 10 g of 20-40 μm of conditioned silica, and then eluted with a mixture (cyclohexane/ethyl acetate), (8/2) (v/v) at a flow rate of 5 ml/minute. The fractions between 30 and 75 ml are concentrated under reduced pressure. 0.1 g of 5,5-dimethyl-1-(2-chloropyrid-4-ylmethyl)-3-(4-trifluoromethoxyphenyl)imidazolidine-2,4-dione is thus obtained in the form of a white powder, the characteristics of which product are as follows:

Quelle