反应 #651102

反应方程式

5-methyl-2-thiophenecarboxaldehyde

nitromethane

HCl

sodium hydroxide

→

title compound

收率 51.0%

2-Methyl-5-((E)-2-nitro-vinyl)-thiophene

收率 51.0%

溶剂

methanol

water

反应条件

后处理

1. 1
   温度wise maintaining the temperature between 5 and 10° C. (formation of a yellow precipitate)
2. 2
   workup.ADDITIONAfter complete addition the mixture
3. 3
   其他The crude product separated as a yellow solid, which
4. 4
   过滤was filtered
5. 5
   workup.DISSOLUTIONdissolved in dichloromethane
6. 6
   干燥The solution was dried over Na2SO4
7. 7
   过滤filtered
8. 8
   浓缩concentrated in vacuo
9. 9
   其他The crude product was purified on a silica eluting with a gradient
10. 10
    其他formed from heptane and ethyl acetate
11. 11
    其他Evaporation of the product fractions

实验过程

A solution of 10.3 g (80 mmol) 5-methyl-2-thiophenecarboxaldehyde (commercially available) and 13.5 mL nitromethane in 160 mL methanol was cooled to −5° C. A 50% sodium hydroxide solution (80 mL) was added drop wise maintaining the temperature between 5 and 10° C. (formation of a yellow precipitate). After complete addition the mixture was stirred at 10° C. for 1 h. The suspension was poured onto an ice-cold solution of HCl 37% (340 mL) and water (560 mL). The crude product separated as a yellow solid, which was filtered and dissolved in dichloromethane. The solution was dried over Na2SO4, filtered and concentrated in vacuo. The crude product was purified on a silica eluting with a gradient formed from heptane and ethyl acetate. Evaporation of the product fractions yielded 6.9 g (51%) of the title compound as yellow solid.

来源