3, 3′-Azothiophene. (January 2013)

• Record Type: Journal Article
• Authors: Glover, Martin; Huddleston, Patrick R.; Wood, Michael L.
• Is Part Of: Journal of chemical research. Volume 37:Number 1(2013)
• Page Start: 43
• Page End: 44
• Publication Date: 2013-01
• Subjects: azothiophene -- azoxythiophene -- hydrazothiophene -- nitrosothiophene; Chemistry -- Research -- Periodicals; Chemistry -- Periodicals; 540.5
• DOI: 10.3184/174751912X13549016589705
• Languages: English
• ISSNs: 1747-5198

Abstract

Methyl 3-nitrothiophene-2-carboxylate was reduced with bismuth(III) chloride/potassium borohydride to give an unstable hydroxylamine which was oxidised without isolation using iron(III) chloride to give methyl 3-nitrosothiophene-2-carboxylate. Condensation of this with methyl 3-aminothiophene-2-carboxylate furnished the azodiester. This was more conveniently obtained by manganese dioxide oxidation of the aminoester. Hydrolysis of the azodiester to give the diacid followed by decarboxylation gave 3, 3′-azothiophene which could be oxidised to 3, 3′- azoxythiophene with hydrogen peroxide. The azodiester was oxidised to the corresponding azoxydiester with urea-hydrogen peroxide/trifluoroacetic anhydride and reduced to the related hydrazothiophenediester with diimide.