Ten optically pure substituted 2-(pyridin-2-yl)imidazolidin-4-ones, 1a-d, 2a-4a, and 2b-4b, were prepared and characterized. The absolute configurations of individual ligands were determined by X-ray analysis or NOESY experiments. The Cu(II) complexes of the respective ligands were studied as enantioselective catalysts of the nitroaldol (Henry) reaction of aldehydes with nitromethane, giving the corresponding substituted 2-nitroalkanols. In the case of an anti arrangement of the imidazolidin-4-one ring, the obtained result was 91-96% ee, whereas in the case of syn arrangement, a significant drop to 25-27% ee was observed.

15N NMR spectra of twelve neat ionic liquids derived from 1,3-disubstituted imidazolium salts were measured, and effects of nitrogen atoms substitution, type of anions and influence of solvents used for dilution of neat ionic liquids were studied. Changes in charge distribution are discussed.

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The reaction of substituted benzenediazonium tetraphenylborates with the β-enaminones derived from pentane-2,4-dione, 1-phenylbutane-1,3-dione, and 1,4-diphenylbutane-1,3-dione with a primary or secondary (N-methyl, N-phenyl) amino group in CH2Cl2 gives 5-(substituted-phenyldiazenyl)-2,2-diphenyl-4,6-disubstituted-1,3,2λ4-oxazaborines or 5-(substituted-phenyldiazenyl)-2,2-diphenyl-3,4,6-trisubstituted-1,3,2λ4-oxazaborines, respectively. The reaction intermediate of these compounds has been identified, and a mechanism for the reaction has been suggested. Substituted 1,3,2λ4-oxazaborines gradually rearrange into 1,2,4,3λ4-triazaborines at temperatures above 100 °C.