Complexes of bicyclic diaziridines 6,6´ bi(1,5 diazabicyclo[3.1.0]hexane) (L 1 ) and 6 (4 methoxyphenyl) 1,5 diazabicyclo[3.1.0]hexane (L 2 ) with the salts Cd(NO 3 ) 2 •4H 2 O and Cd(ClO 4 ) 2 •6H 2 O have been synthesized. The fact of complexation has been established by cyclic voltammetry. The crystal structure of complex L 1 with Cd(NO 3 ) 2 (the coordination number of cadmium is 8) has been studied by X ray diffraction.

Reactions of 1,3 diphenylpropen 2 one and β nitrostyrenes with azomethine imines, generated from 6 aryl 1,5 diazabicyclo[3.1.0]hexanes on catalysis with Et 2 O•BF 3 in ionic liquids, were found to proceed with high regio and stereoselectivity to afford the products of the diaziridine ring expansion, viz., [3 aryl 2 phenyltetrahydro 1H,5H pyrazolo[1,2 a]pyrazol 1 yl](phenyl)methanones, 1,3 diaryl 2 nitrotetrahydro 1H,5H pyrazolo[1,2 a]pyrazoles and 5 aryl 6 (3 nitrophenyl) 2,3 dihydro 1H pyrazolo[1,2 a]pyrazolium tetrafluoroborates (hexafluorophosphates). The reactions discovered are new, more simple methods for the syn thesis of bicyclic structures.

A reaction of aryl ketenes with 1 arylmethylidenepyrazolidin 1 azomethine imines, gen erated by the diaziridine ring opening in 6 aryl 1,5 diazabicyclo[3.1.0]hexanes catalyzed with Et 2 O•BF 3 , leads to 1,2 bis(phenylacetyl)pyrazolidine, 2 arylacetyl 1 arylidenepyrazolidin 1 ium chlorides, or a representative of 1,5 diazabicyclo[3.3.0]octan 2 ones, viz., 4 (4 eth oxyphenyl) 3,3 diphenyl 1,5 diazabicyclo[3.3.0]octan 2 one, depending on the reaction con ditions and the structure of the starting compounds. A mechanism suggested earlier for the transformation of 1,5 diazabicyclo[3.1.0]hexanes in the reaction with ketenes was confirmed.

The present study revealed two new reactions resulting in the diaziridine ring expansion, viz., the insertion of the CS 2 molecule and the CN group of activated nitriles into the C-N bond of the diaziridine fragment of 6 aryl 1,5 diazabicyclo[3.1.0]hexanes. These reactions can be performed only in ionic liquids in the presence of BF 3 •Et 2 O as the catalyst. Based on these reactions, we developed simple one pot methods for the synthesis of 3 aryldihydro 5H pyrazolo[1,2 c][1,3,4]thiadiazole 1 thiones and 1 aryl 6,7 dihydro 1H,5H pyrazolo [1,2 a] [1,2,4]triazoles in high yields. Dipolar intermediates of new reactions, which are direct precursors of the final products, were detected by NMR methods. One of the intermediates was isolated and characterized. The reaction of 6 aryl 1,5 diazabicyclo[3.1.0]hexanes with benzoyl cyanide affords (2 benzoylpyrazolidin 1 yl)(aryl)acetonitriles.

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