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Chitosan copper (II) oxide nanocomposite was synthesized, characterized and used to synthesize [1,2,3]triazoles. Nanocomposite was characterized by using FTIR, XRD, FESEM, and EDS techniques, which reflected rough morphology. The powerful catalytic activity of hybrid nanocomposite was utilized to synthesize chalcones (3a-p) in relatively high yields (82%-98%) and multicomponent regio-selective cycloaddition of chalones, aryl halides (4), and sodium azide to afford the expected N-2-aryl[1,2,3]triazoles (5a-h) (80%-95% yield) rather than N-1-aryl[1,2,3]-triazoles (6a-h). The performance of nanomaterial was optimized by several variables. The capability of the nanocomposite was compared with previous work and the nanocomposite was found more efficient, economic and reproducible. The hybrid nanocomposite could be easily isolated form the reaction mixture and recycled four times without any significant loss of its catalytic activity. The reported catalyst is an inexpensive for good yields of the triazoles and may be used at industrial production for the reported compounds.

1,3-Dipolarcycloaddition reactions of 6-arylmethylene-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-ones (1) with nitrilimines 3 were investigated in benzene and chloroform. The reaction products were 2′,4′,6,7,8,9-hexahydro-2′,4′,5′-triaryl spiro[benzocycloheptene-6(5H),3′(3H-pyrazol)-5-ones (4) or 2′,3′,6,7,8,9-hexahydro-2′,3′,5′-triaryl spiro[benzocycloheptene-6(5H),4′(4H-pyrazol)-5-ones (5). X-ray crystallographic analysis was carried out for compound 5b. It was found that the regioselectivity of the produced compounds was altered based on changing solvent type.

Electrochemical fluorination of 2-alkylthio-4-methyloxazoles has been successfully carried out using Et4NF·nHF (n=4, 5) as the supporting electrolyte and fluoride source to provide the corresponding 2-alkylthio-4,5-difluoro-4-methyl-2-oxazolines, and fluorination did not take place at α to the sulfur atom. In the case of electrochemical fluorination of 2-methylthio-4-cabomethoxyoxazole afforded a 2,5-difluoro-3-oxazoline derivative in addition to a 4,5-difluoro-2-oxazoline one. In contrast, anodic fluorination of 2,4,5-trimethyloxazole devoid of a thio group resulted in no formation of fluorinated products.

Aryl propargyl sulfides were subjected to electrochemical fluorination in dimethoxyethane (DME) containing various fluoride supporting electrolytes using an undivided cell to provide the corresponding α-monofluorinated or α,α-difluorinated sulfides selectively as main products in good yields depending on the amount of electricity passed. The α,α-difluorinated sulfides were stable enough to be isolated while the α-monofluorinated ones were very unstable. The α-monofluorinated sulfides were readily converted into the corresponding stable α-monofluoroallenyl sulfides in good yields. Furthermore, synthetic utility of α-monofluoroallenyl sulfides was also investigated.

Anodic fluorination of various nitrogen-containing heterocyclic propargyl sulfides using Et4NF·nHF (n=3,4) or Et3N·3HF as a supporting electrolyte and fluoride ion source in dimethoxyethane provided the corresponding monofluorinated products in moderate yields. Fluorination took place selectively at the position α to the sulfur atom of the sulfides and the heterocyclic moieties were not fluorinated at all.

The anodic fluorination of aryl propargyl sulfides in DME containing a fluoride supporting electrolyte using an undivided cell provided the corresponding α-mono- and α,α-difluorinated sulfides selectively, depending on the amount of electricity passed. The α-monofluorinated sulfides were readily converted into the corresponding α-fluoroallenyl sulfides in good to moderate yields.