反应详情

温度

30 °C

45 g of 5-nitro-3-benzothiophencarboxylic acid were suspended in 150 ml of 1,1,1-trichloroethane. 100 ml of thionyl chloride and 0.5 ml of DMF were added. The mixture was refluxed for 2 hours resulting in a clear solution. The solvents were evaporated and remaining thionyl chloride was removed by evaporation twice with toluene. The crystalline product thus obtained was added in small portions to a solution of 60 g of dipropylamine in 500 ml of dichloromethane below 10° C. The mixture was heated to 30° C. and eluted through 200 g of silica gel with 1500 ml of a mixture (1:1) of dichloromethane and ethyl acetate. The organic phase was washed with water, dried (MgSO4) and evaporated. 200 ml of n-heptane were added and the crystalline product filtered off. Yield: 56 g. M.P. 100° C.

1. temperatureThe mixture was refluxed for 2 hours
2. customresulting in a clear solution
3. customThe solvents were evaporated
4. customwas removed by evaporation twice with toluene
5. customThe crystalline product thus obtained
6. washeluted through 200 g of silica gel with 1500 ml of a mixture (1:1) of dichloromethane and ethyl acetate
7. washThe organic phase was washed with water
8. dry with materialdried (MgSO4)
9. customevaporated
10. addition200 ml of n-heptane were added
11. filtrationthe crystalline product filtered off