Ferrocenecarboxylic acid and microwave-assisted synthesis of ferrocenoyl hydrazones

A protocol to access ferrocenecarboxylic acid via carboxylation of ferrocene with carbon dioxide in the presence of aluminum chloride was elaborated. An efficient microwave-assisted synthesis of ferrocenoyl hydrazones by condensation of ferrocene carbohydrazide with carbonyl compounds was developed. Structures of the synthesized compounds were examined by NMR spectroscopy and mass spectrometry. Structures of N ´-(4-chlorobenzylidene)ferrocenecarbohydrazide, N ´-(4-methoxybenzylidene)ferrocenecarbohydrazide, and N ´-(2-hydroxybenzylidene)ferrocenecarbohydrazide were determined by X-ray diffraction analysis. Synthesized compounds were found to have no toxicity against P. aeruginosa , E. coli , S. aureus , B. subtilis , M. rubrum , and C. albicans .