Online article for Non-subscribers

Pay per view

Heterocycles has a pay-per-view service for Non-subscribers.
You will be able to directly purchase the full text article through PayPal.
Your purchased Paper can be downloaded after the payment is completed.
An e-mail will be sent the URL to download the paper.
If you have any questions, please contact: purchase@heterocycles.com

Price: ¥ 4,320 (Yen only)
Period: This Article can be accessed for 7 days.

Note | Regular issue | Vol 63, No. 7, 2004, pp.1629-1635
Published online, 21st May, 2004
DOI: 10.3987/COM-04-10069
Synthesis of a New Imidazo[4,5-b]pyridin-5-one via a Vicarious Nucleophilic Substitution of Hydrogen

Maxime D. Crozet, Clément Suspène, Mustapha Kaafarani, Michel P. Crozet, and Patrice Vanelle*

*Laboratory of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, CNRS UMR, University of the Méditerranée (Aix-Marseille 2), 27 Bd Jean Moulin, 13385 Marseille cedex 5, France

Abstract

A new imidazo[4,5-b]pyridin-5-one was prepared in five steps from 4(5)-nitro-1H-imidazole via a vicarious nucleophilic substitution of hydrogen of 1-benzyl-4-nitro-1H-imidazole with the carbanion generated from chloroform and potassium tert-butoxide. Hydrolysis of 1-benzyl-5-dichloromethyl-4-nitro-1H-imidazole and Knoevenagel condensation between the resulting aldehyde and diethyl malonate catalyzed by titanium(IV) chloride gave the corresponding 4-nitroimidazole bearing at 4 position the diethyl methylenemalonate group.Å@Reduction and cyclization afforded the required ethyl 1-benzyl-5-oxo-4,5-dihydro-1H-imidazo[4,5-b]pyridine-6-carboxylate.