| Summary: | The objective of this Thesis was to prepare dialkynenitriles 156 and 168 for the synthesis of aza[6]helicene 146 and 147 via intramolecular [2+2+2] co-cyclotrimerization. It was found that it is possible to use co-cycloisomerization of alkynedinitriles 182, 187, 192 and 195, a reaction so far not described in the literature, for the preparation of dibenzodiazahelicenes 148 and 149 and dioxadiazahelicenes 150 and 151 possessing a pyridazine subunit. Moreover, alkynedinitriles 152, 153, 154 and 155 were synthesized to further study of this co-cycloisomerization reaction. The Theoretical Part outlines some representative examples of methods for the preparation of azahelicenes and azoniumhelicenes, current development of [2+2+2] cocyclotrimerization in the synthesis of pyridine derivatives and methods of pyridazine synthesis. The syntheses of dialkynenitriles 156 a 168, diazahelicenes 148, 149, 150, 151 and alkynedinitriles 152, 153, 154 and 155 are described in the section Results and Discussion and Experimental Part.
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