In this master's degree I have synthesized eight variously substituted bicyclo[2.2.2]octene systems by using Diels–Alder cycloaddition of maleic anhydride on differently substituted 2H-pyran-2-ones. In the first stage of the cycloaddition of maleic anhydride as the dienophile oxabicyclo[2.2.2]octene intermediates are formed, which under the reaction conditions spontaneously eliminate a molecule of carbon dioxide and thus form the next cyclohexadiene intermediate, which serves as the diene for the attack of the second molecule of dienophile (maleic anhydride). Using molecular modelling I explored the endo/exo attack preference of various dienophiles (maleic anhydride and substituted vinyl ethers) of the first stage of the cycloaddition reaction. I compared the results, obtained with the computational method PM6, with experimental data in the literature.
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