反应详情

To 6.73 g. (0.05 mole) of 1-methyl-2-iminopyrrolidine HCl is added 1 ml. of water and 50 ml. of benzene. After solution is complete (magnetic stirring), 10 ml. of aqueous sodium hydroxide (50%) is added in one portion. After stirring for about 1 min., the benzene layer is decanted onto anhydrous potassium carbonate. The extraction is repeated twice. After drying (occasional swirling) the combined benzene extracts are filtered (dicalite) from drying agent and 9.4 g. (0.05 mole) of 2,5-dichlorophenylisocyanate is added to the filtrate in one portion with swirling. After stirring for 3 hours, the solvent is removed in vacuo affording a colorless solid 1-(2,5-dichlorophenyl)-3-(1-methyl-2-pyrrolidylidene)urea. Recrystallization from acetone (twice) yields the pure product, m.p. = 148.5°-150.5° C.

1. stirringAfter stirring for about 1 min.
2. customthe benzene layer is decanted onto anhydrous potassium carbonate
3. extractionThe extraction
4. dry with materialAfter drying (occasional swirling) the combined benzene extracts
5. filtrationare filtered (dicalite)
6. customfrom drying agent and 9.4 g
7. stirringAfter stirring for 3 hours
8. customthe solvent is removed in vacuo