imidazolidine

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A quantity of 8.9 gm of 1-propargyl-2-(2-bromo-6-fluorophenylimino)-imidazolidine was refluxed in 60 ml of absolute ethanol for about 11 hours. Then the solvent was eliminated in vacuo, and the remaining residue was dissolved in dilute (approximately 1N) hydrochloric acid. The imidazolidine derivative used (identified by thin layer chromatography) was then eliminated by fractional extraction with ethyl acetate at increasing pH values (rendered alkaline with 2N NaOH). As soon as the starting imidazolidine has been quantitatively removed, the imidazo[1,2-a]imidazole derivative according to the invention was extracted as the pH values increased still further (carefully rendered alkaline with 2N NaOH in stages). After being checked by thin layer chromatography, the individual extracts were combined and dried over anhydrous calcium sulfate, and the solvent was eliminated in vacuo. the remaining residue was dissolved was then eliminated by fractional extraction with ethyl acetate at increasing pH values (rendered alkaline with 2N NaOH) As soon as the starting imidazolidine has been quantitatively removed was extracted as the pH values increased still further (carefully rendered alkaline with 2N NaOH in stages) dried over anhydrous calcium sulfate