| Abstract [eng] |
The bicyclo[3.3.1]nonane derivatives are known to be embodied in the structure of a diverse variety of natural products and are important intermediates in the synthesis of complex molecular structures. In contrast to rather well developed synthetic chemistry of bicyclo[3.3.1]nonanes, the examples of the application of these compounds in supramolecular chemistry are very scarce to mention lattice inclusion hosts, crown ethers, etc. The unique V-shape of the bicyclic scaffold is obtained fusing the cyclohexane rings with aromatic(heteroaromatic) units. The geometric features may be combined with the chirality of the system, resulting from the functionalization of bicyclic core at proper positions. The aim of this thesis is to explore stereochemical multiplicity of the bicyclo[3.3.1]nonane framework for the construction of chiral, C2-symmetric supramolecular preprogrammed synthons containing hydrogen bonding recognition patterns at both ends of the molecule. The resulting cleft molecules would be utilized for the formation of tubular structures via end-to-end association of these synthons. The synthesis of important intermediate, bicyclo[3.3.1]nonane-2,6-dione, was improved up to 50% comparing to existing procedures and the reaction was successfully adopted to large scale preparation. The large scale dynamic kinetic resolution of bicyclo[3.3.1]nonane-2,6-dione was achieved by using Baker’s yeast for sweet dough overcoming difficulties associated with the use of ordinary Baker’s yeast enabling the synthesis of up to 45 g of enantiomerically pure (+)-(1S,5S)-bicyclo[3.3.1]nonane-2,6-dione. General synthetic strategies leading to three generations of novel chiral cleft molecules were developed by fusing bicyclo[3.3.1]nonane framework with heteroaromatic rings containing two, three and four hydrogen bonding complementary modules. In addition, the general synthetic procedure for racemic azabicyclo[ 3.3.1]nonane analogues, containing isocytosine moiety, was developed. The first generation cavity compound, containing 2-pyridone hydrogen bonding unit forms tubular assemblies of moderate size (up to 10 molecules in CD2Cl2) in solution. The association is best described by using isodesmic model, and the association constants were estimated to be KE= 1142±162M-1 and KE=105±9.2M-1 at 299K in CD2Cl2 and CDCl3, respectively. The change in enthropy and enthalpy of the association was estimated to be -20.3±1.2 kJ mol-1 and -29.1±4.2 J mol-1 K, respectively. The obtained values agree well with those of parent 2-pyridone, indicating non-cooperative association. The second generation compound, containing isocytosine unit, forms very stable hydrogen bonded tetramers via self-complementariness of its two tautomeric forms. The new term, tautoleptic aggregation, is introduced for describing this type of aggregation. The supramolecular tetramer undergoes reversible stacking in non-polar solvents resulting in tubular structure. The preference for the formation of tetramer or stacked polymer depends on the bulkiness of substituent on the bicyclic moiety. Preliminary results show that the cavity of the tetramer is well suited to encapsulate C60 molecules. 33 The aggregation of third generation compound, containing quadruple 2-ureido pyrimidinone module is limited to the formation of dimers and trimers only. The small degree of association is attributed to steric crowding in the assembly implied by bulky solubilizing groups. The CD spectroscopic studies of chiral bicyclo[3.3.1]nona-3,7-diene-2,6-dione shows that trans-orbital interaction of enone chromophores is taking place resulting in increase of n→π* transition intensity. The octant rules was applied for the analysis of bicyclic enones. The network approach for the analysis of the crystal structure of bicyclo[3.3.1]nonane derivatives was applied and proved to be a good method for understanding and comparing weak interactions in this type of compounds. Previously unknown type of chiral network, (82.12)-utg net, was found in the crystal structure of endo,endo-bicyclo[3.3.1]nonane-2,6-diol. The introduction of double bond into bicyclic structures resulted in predominance of 2D networks. |
