In the first phase of my master's thesis, I synthesized a variety of bicyclo[2.2.2]octenes from suitably substituted 2H-pyran-2-ones and maleimide. The reactions were took place according to the well known Diels–Alder cycloadditions. The prepared bicyclo[2.2.2]octenes represented the starting reactant in the following step of N-halogenation reaction where I tried to form a bond between a halogen (chlorine) and a ring nitrogen. By appropriate modifications of the literature reaction conditions, I developed environmentally friendly N-chlorination, using NaCl, which was the source of chlorine, oxone as the oxidant, solid Al2O3, and chloroform as the solvent. The reactions were carried out in closed ACE tubes at 45 °C. By changing the reaction parameters I managed to successfully synthesize three new N,N'-dichloro derivatives of fused bicyclo[2.2.2]octene systems.
In the second phase of the experimental work, I tried to prepare co-crystals from previously synthesized N-halogenated bicyclo[2.2.2]octenes and suitable pyridine derivatives, which would presumably contain halogen bond, using 2,2'-bipyridyl and 4,4'-bipyridyl, as the halogen bond acceptors. Preparation of such crystals would allow further investigations into the nature of halogen bonding. Unfortunately, the preparation of the crystals was not successful.
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