Green and fast procedure to obtainN-alkylbenzimidazole derivatives under microwave activation

• Published in: Environmental progress & sustainable energy Vol. 30; no. 3; pp. 469 - 475
• Main Authors: Calvino-Casilda, V., Martín-Aranda, R.M., López-Peinado, A.J.
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01-10-2011
• Subjects: basic carbons; green chemistry; microwave activation; N-alkylbenzimidazole derivatives
• ISSN: 1944-7442; 1944-7450; 1944-7450
• DOI: 10.1002/ep.10491

In this research, we report for the first time the one‐pot microwave‐assisted synthesis of N‐butylbenzimidazole derivatives via alkylation of benzimidazole with 1‐bromobutane over alkali‐metal doped carbons in absence of any solvent. N‐alkylbenzimidazole derivatives are produced in high yields and in very short reaction times when NaCs‐Norit is used as catalyst (ca. 75% in 5 min). Thus the combination of microwaves and basic carbons in dry media leads to the simplest, most eco‐efficient and fastest procedure reported so far for the preparation of benzimidazole derivatives with pharmacological properties. Under these mild reaction conditions, N‐butylbenzimidazoles are obtained with total selectivity to be used in many important industrial applications. © 2010 American Institute of Chemical Engineers Environ Prog, 2011