A. N. Rodionov

Ferrocene modification of organic compounds for medicinal applications

The results of the authors on the synthesis of ferrocene-containing organic compounds obtained in 1998–2013 are summarized. The review is focused on the ferrocene modifications of purine and pyrimidine bases, thiopyrimidines, natural and synthetic amino acids, azoles (including polyfluoroazoles and mercaptoazoles) and ferrocenyl quinoline synthesis. The special attention is given to the scale synthesis of compounds for biological trials.

Ethyl 5-ferrocenyl-1H-pyrazolecarboxylates: The synthesis and redox properties

Redox potentials of isomeric ethyl 5-ferrocenyl-1H-pyrazole-3-carboxylates 2 and ethyl 5-ferrocenyl-1H-pyrazole-4-carboxylates 4 were measured and their dependences on the acidity of the medium were determined. The structures of various conformers of neutral molecules and corresponding radical cations were calculated by the B3LYP/6-31G* method. The results of calculations for neutral molecules were confirmed by X-ray data.

Synthesis of N-ferrocenylalkylated pyrazole derivatives

Carbonyl derivatives of N-ferrocenyl alkyl pyrazoles were synthesized. The techniques of analytical separation of racemates of the synthesized compounds were developed. The structures of three compounds were determined by X-ray diffraction analysis.

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.

Synthesis and properties of N-ferrocenylalkylated pyrroles

A series of N-ferrocenylalkyl pyrroles were synthesized by intermolecular redox amination of ferrocenyl ketones and formylferrocene with pyrroline. The racemic mixtures were separated into enantiomers using high performance liquid chromatography. The structure of N-ferrocenylmethylpyrrole was determined by X-ray diffraction.

Ferrocene-containing tri- and tetranuclear cyclic copper( i ) and silver( i ) pyrazolates

New tri- and tetranuclear macrocyclic silver(i) and copper(i) 3-ferrocenyl-5-(trifluoromethyl)pyrazolates were prepared: [{(3-((η5-C5H4)Fe(η5-C5H5))-5-(CF3)-Pz}M]3 (M = Cu (1), Ag (2)) and [{(3-(( η5-C5H4)Fe(η5-C5H5))-5-(CF3)-Pz}Cu]4 (3). The structures of compounds were established by X-ray diffraction analysis. In the crystalline state, a planar trinuclear silver-containing macrocycliс pyrazolate and a saddle-shaped tetranuclear copper-containing macrocycle are formed. The introduction of a bulky substituent, ferrocene, into the pyrazole ligand results in complete shielding of the acidic metal sites, which precludes the coordination of base molecules.

Synthesis of ferrocenyl-containing heterocyclic derivatives of 5-(4-aminophenyl)-10,15,20-triphenylporphyrin for sonodynamic therapy

The condensation of 1-(ferrocenylalkyl)pyrazole-3-carbaldehydes with 4′-aminotetraphenylporphyrin, followed by reduction with NaBH(OAc)3 in 1,2-dichloroethane, provides a convenient method for the synthesis of 5-{4-[({1-[1-(ferrocen-1-yl)alkyl]-5-methyl-1H-pyrazol-3-yl}methyl)amino]phenyl}-10,15,20-triphenylporphyrins which exhibit pronounced cytotoxicity against Staphylococcus aureus under ultrasonic irradiation.

Dicarbonyl chelates from 1-cymantrenylalkylamides with the dendrite structure: formation, photochromism, and kinetics of dark reaction with carbon monoxide

Photolysis of carboxamides of the dendrite structure with aminomethyland 1-aminoethylcymantrenes leads to the formation of six-membered dicarbonyl chelates with the Mn—O bond which are stable in solutions. The chelates in the reversed dark reaction with carbon monoxide give the starting tricarbonyl complexes. The formation of the chelates and their dark reaction are accompanied by the reversible change of color by the compounds. The rate determining step of the thermal reaction of chelates with CO is a chelate ring opening with the ligand substitution by the SN1 mechanism. A possibility of solvent-free photoinduced ligand-exchange reaction in a number of cymantrene derivatives was demonstrated.

The synthesis of ferrocenyl- and ferrocenoylpyrimidines

New derivatives of pyrimidine were synthesized from ferrocenyl ketones by the reactions of [3+1+1+1]annulation and intermolecular cyclization. The electrochemical behavior of the obtained compounds was studied by the method of cyclic voltammetry. All the compounds may be characterized with the signal, corresponding to the reversible one-electron transfer in ferrocene-ferrecinium and lowering of the redox potential with respect to ferrocene.