中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
3-硝基噻吩-2-羧酸甲酯 | Methyl 3-nitrothiophene-2-carboxylate | 75735-44-3 | C6H5NO4S | 187.176 |
—— | Methyl 3-(hydroxyamino)thiophene-2-carboxylate | —— | C6H7NO3S | 173.192 |
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.