New Approaches to the Synthesis of 4-(2-Aminophenyl)-1,3-dihydro-2H-imidazol-2-ones and 3-Ureidoindoles and a Study of Their Interconversion

✍ Scribed by Antonín Klásek; Antonín Lyčka; Michal Holčapek; Ignác Hoza

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: German
• Weight: 272 KB
• Volume: 91
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.200890040

✦ Synopsis

Abstract

3‐Alkyl/aryl‐3‐ureido‐1__H__,3__H__‐quinoline‐2,4‐diones (2) and 3a‐alkyl/aryl‐9b‐hydroxy‐3,3a,5,9b‐tetrahydro‐1__H__‐imidazo[4,5‐c]quinoline‐2,4‐diones (3) react in boiling concentrated HCl to give 5‐alkyl/aryl‐4‐(2‐aminophenyl)‐1,3‐dihydro‐2__H__‐imidazol‐2‐ones (6). The same compounds were prepared by the same procedure from 2‐alkyl/aryl‐3‐ureido‐1__H__‐indoles (4), which were obtained from the reaction of 3‐alkyl/aryl‐3‐aminoquinoline‐2,4(1__H__,3__H__)‐diones (1) with 1,3‐diphenylurea or by the transformation of 3a‐alkyl/aryl‐9b‐hydroxy‐3,3a,5,9b‐tetrahydro‐1__H__‐imidazo[4,5‐c]quinoline‐2,4‐diones (3) and 5‐alkyl/aryl‐4‐(2‐aminophenyl)‐1,3‐dihydro‐2__H__‐imidazol‐2‐ones (6) in boiling AcOH. The latter were converted into 1,3‐bis[2‐(2‐oxo‐2,3‐dihydro‐1__H__‐imidazol‐4‐yl)phenyl]ureas (5) by treatment with triphosgene. All compounds were characterized by ^1^H‐ and ^13^C‐NMR and IR spectroscopy, as well as atmospheric pressure chemical‐ionisation mass spectra.