反应详情

A solution of 17.5 g. (0.1 mole) ρ-chlorobenzoyl chloride and 13.3 g. (0.1 mole) aluminum chloride in 150 ml. of dichloroethane is added rapidly to a solution of 25.3 g. (0.1 mole) of ethyl 1.4-dimethyl-3-ethoxycarbonylpyrrole-2-acetate in 100 ml. of refluxing 1,2-dichloroethane. The solution is refluxed for 3.5 hours and poured into ice-hydrochloric acid. The organic layer is separated, and the aqueous layer washed with 1,2-dichloroethane. The combined organics are washed successively with water, N,N-dimethylaminopropylamine, dilute HCl and brine. The solution is then dried over anhydrous magnesium sulfate, and the solvent evaporated in vacuo. The residue product is crystallized from cyclohexane and recrystallized from methanol to give ethyl 5-(ρ-chlorobenzoyl)-1,4 dimethyl-3-ethoxycarbonylpyrrole-2-acetate as a white solid, M.P. 91°-93° C.

1. temperatureThe solution is refluxed for 3.5 hours
2. customThe organic layer is separated
3. washthe aqueous layer washed with 1,2-dichloroethane
4. washThe combined organics are washed successively with water, N,N-dimethylaminopropylamine, dilute HCl and brine
5. dry with materialThe solution is then dried over anhydrous magnesium sulfate
6. customthe solvent evaporated in vacuo
7. customThe residue product is crystallized from cyclohexane
8. customrecrystallized from methanol