Summary.
Different reactivities towards the 4H-imidazoles 1 depending on the nature of the sulfur containing nucleophile were observed. Whereas H2S and aromatic thioles led to 4,5-diaminoimidazoles in the course of a reduction process, treatment with aliphatic mercaptanes resulted in a substitution-reduction-dimerization cascade which finally gave bis-imidazoles. Their oxidative modification in presence of m-chloroperbenzoic acid then allowed new 1,3,5,7-tetraazafulvalenes to be easily obtained. Treatment of the bis-imidazoles with acetylene dimethyldicarboxylate caused cleavage of the central bond, thus leading to the formation of derivatives which are of interest for the transformation into fused heterocycles such as imidazo[4,5-b]azepines.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received May 22, 2000. Accepted June 19, 2000
Rights and permissions
About this article
Cite this article
Atzrodt, J., Beckert, R. & Görls, H. Nucleophilic Substitution of 4H-Imidazolesby Thioles: New Starting Materials for Tetraazafulvalenes and Fused Heterocycles. Monatshefte fuer Chemie 131, 1181–1190 (2000). https://doi.org/10.1007/s007060070026
Issue Date:
DOI: https://doi.org/10.1007/s007060070026