반응 #1147

반응 방정식

Sodium hydride

6-(5-methyl-2-phenyl-4-oxazolylmethoxy)benzofuran-2-carbaldehyde

diethyl cyanomethylphosphonate

hydrochloric acid

→

2-(2-cyanoethyl)-6-(5-methyl-2-phenyl-4-oxazolylmethoxy)benzofuran

수율 83.1%

용매

N,N-dimethylformamide

반응 조건

후처리

1. 1
   추출followed by extraction with ethyl acetate (200 ml)
2. 2
   세척After the ethyl acetate layer was washed with water
3. 3
   건조dried (MgSO4), palladium-carbon (5%, 0.70 g)
4. 4
   workup.ADDITIONwas added
5. 5
   기타followed by catalytic reduction at room temperature under an atmospheric pressure of 1 atm
6. 6
   여과After the catalyst was filtered off
7. 7
   농축the filtrate was concentrated
8. 8
   세척From the fraction eluted with ethyl acetate-chloroform (2:98

실험 절차

Sodium hydride (60%, oily, 0.20 g) was gradually added to a solution of 6-(5-methyl-2-phenyl-4-oxazolylmethoxy)benzofuran-2-carbaldehyde (1.50 g) and diethyl cyanomethylphosphonate (0.88 g) in N,N-dimethylformamide (30 ml) at 0° C., followed by stirring at room temperature for 1 hour. The reaction mixture was poured over ice water and neutralized with 2N hydrochloric acid, followed by extraction with ethyl acetate (200 ml). After the ethyl acetate layer was washed with water and dried (MgSO4), palladium-carbon (5%, 0.70 g) was added, followed by catalytic reduction at room temperature under an atmospheric pressure of 1 atm. After the catalyst was filtered off, the filtrate was concentrated; the residue was subjected to silica gel column chromatography. From the fraction eluted with ethyl acetate-chloroform (2:98, v/v), crystals of 2-(2-cyanoethyl)-6-(5-methyl-2-phenyl-4-oxazolylmethoxy)benzofuran (1.34 g, 83%) were obtained, which was then recrystallized from dichloromethane-hexane to yield colorless prisms having a melting point of 92° to 93° C.

출처