反应详情

41.4 g of N-hydroxymethyl-3-(2-chlorophenyl)-4-cyanopyrrole are dissolved in 350 ml of pyridine and 1.8 g of dimethylaminopyridine are added. Then 21.4 ml of acetic anhydride are slowly added dropwise at 0° to 7° C. and the mixture is stirred for 12 hours. The reaction mixture is then poured into ice-water and extracted twice with ethyl acetate. The extracts are washed twice with dilute ice-cold hydrochloric acid and twice with a semi-saturated aqueous solution of sodium chloride, dried over sodium sulfate and filtered. The filtrate is concentrated and the residue is recrystallised from diethyl ether/hexane to give the title compound in the form of colourless crystals with a melting point of 91°-95° C.

1. extractionextracted twice with ethyl acetate
2. washThe extracts are washed twice with dilute ice-cold hydrochloric acid and twice with a semi-saturated aqueous solution of sodium chloride
3. dry with materialdried over sodium sulfate
4. filtrationfiltered
5. concentrationThe filtrate is concentrated
6. customthe residue is recrystallised from diethyl ether/hexane