1.     Quantum-chemical method DFT B3LYP/6-311G* was applied to stage by stage thermodynamic calculation of reactions of electrophilic iodination of benzene, naphthalene, phenanthrene, and anthracene with iodine and iodine monochloride, and comparison with chlorination reactions was performed. The main distinction of iodination process from chlorination was an enhanced reversibility owing to protodeiodination. The reversibility of iodination grows with the electron-donor properties of aromatic substrates. The calculations permit an assumption that the chlorination of anthracene and phenanthrene with iodine monochloride occurs most probably through stages of electrophilic iodination-dehydroiodination.

2.     The results of reactions of a series of aromatic substrates with iodine, iodine(I) chloride, and N-iodosuccinimide in solution and solid phase were compared for the first time. In all cases, the general relations holding in the iodination process were similar. Iodine(I) chloride was found to chlorinate anthracene. A high efficiency of solid-phase iodination of β-diketones was demonstrated using dibenzoylmethane as an example.

3.     A simple one-step synthesis of iodopyridines and iodobenzothiazoles via the diazotization-iodination of available aminopyridines and aminobenzothiazoles by NaNO₂/H₃PO₄/KI system in t-BuOH was developed. This method provides good yields in general of hard-to-reach iodoheterocycles. It was shown that the methanol and ethanol are unsuitable for diazotitrovaniya-iodination (low conversion of starting aminopyridine 1, the formation of undesirable reduction products). Best results were obtained using tert – butyl alcohol as the reaction solvent diazotization-iodination of aminopyridine 1, yield the desired 5-bromo-2-iodopyridine 32 % (by GC-MS), but 5-bromopyridine-2-yl 4-methylbenzenesulfonate, a side product of interaction with p-toluenesulfonic acid, still remains predominant. Thus, we have shown that the hard-iodopyridine and iodbenztiazoly can be successfully prepared by the reaction of diazotization-iodination of the corresponding aminoheterocycle in slightly acidic nonaqueous media under the infl uence of H₃PO₄/NaNO₂/KI / tert – butanol.