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A convenient method for arylation of mono- and disubstituted 1,2,3-triazoles by copper-catalyzed Chan-Lam coupling was developed. The method is applicable for the regioselective synthesis of fluorescent 4-halogen-substituted (Hal = F, Cl, Br) 2,5-diaryl-1,2,3-triazoles in high yields. Comparative study of their fluorescent properties revealed that 4-fluorosubstituted triazoles possess the highest quantum yield (up to 0.69) among halogenated triazoles possessing Cl and Br in the position 4.

A new method was developed for the synthesis of fully substituted 3-haloisoxazoles. This process includes the synthesis of isoxazoline N-oxides from α-halonitroalkenes and subsequent dehydration mediated by the silyl triflate/triethylamine system.

The [3+3]-cycloaddition of cyclopropane dicarboxylates with 3-methyl-5,6-dihydro-4H-1,2-oxazine-N-oxides promoted by Yb(OTf)3 under hyperbaric conditions is described. The substrates scope and reaction mechanism are discussed.

Silyl nitronates obtained in situ from the corresponding aliphatic nitro compounds react with dimethylformamide dimethyl acetal giving 2-nitroenamines in moderate to good yields. The reaction pathway is discussed.

A new approach toward the synthesis of 3-α-hydroxyalkyl-5,6-dihydro-4H-1,2-oxazines 1 from available 5,6-dihydro-4H-1,2-oxazine N-oxides 2 has been described. The key step of the process—the rearrangement of 3-alkiliden-2-siloxy-tetrahydro-1,2-oxazines 3 (ASENA)—was thoroughly investigated. Optimal experimental conditions were developed. A possible pathway of the ASENA rearrangement was proposed.