반응 #55629

반응 방정식

1,5-Diazabicyclo[5,4,0]-undec-5-ene

nitromethane

methyl crotonate

→

methyl 3-methyl-4-nitrobutanoate

수율 66.2%

용매

methanol

methanol

반응 조건

후처리

1. 1
   기타is removed in vacuo
2. 2
   workup.ADDITIONThe residue is treated with ether (500 ml)
3. 3
   세척washed with 2 N hydrochloric acid (250 ml) and water (250 ml)
4. 4
   건조The organic layer is dried (Na2SO4)
5. 5
   기타evaporated in vacuo
6. 6
   기타to give crude product
7. 7
   기타The crude product is purified by column chromatography on silica gel (500 g, ethyl acetate/hexane 2:98)

실험 절차

1,5-Diazabicyclo[5,4,0]-undec-5-ene (6 ml) is added to a solution of nitromethane (91.5 g) in methanol (500 ml). The resulting mixture is heated to 60° C. and methyl crotonate (100 g, lm) is added under nitrogen. The mixture is then stirred for 6 days at 60° after which it is cooled to room temperature and most of the methanol is removed in vacuo. The residue is treated with ether (500 ml) and washed with 2 N hydrochloric acid (250 ml) and water (250 ml). The organic layer is dried (Na2SO4) and evaporated in vacuo to give crude product. The crude product is purified by column chromatography on silica gel (500 g, ethyl acetate/hexane 2:98) to give methyl 3-methyl-4-nitrobutanoate (106.6 g, 66%).

출처