| Popis: |
V okviru magistrske naloge sem sintetiziral osem različno substituiranih biciklo[2.2.2]oktenskih sistemov z dvojno termično Diels–Alderjevo cikloadicijo maleinanhidrida na različno substituirane 2H-piran-2-one. V prvi stopnji s cikloadicijo maleinanhidrida v vlogi dienofila nastanejo oksabiciklo[2.2.2]oktenski intermediati, ki pod reakcijskimi pogoji spontano eliminirajo molekulo ogljikovega dioksida in tako tvorijo naslednji cikloheksadienski intermediat, ki služi kot nov dien za napad nove molekule dienofila (maleinanhidrida). Z molekulskim modeliranjem sem raziskal ali je v prvi stopnji cikloadicij različnih dienofilov (maleinanhidrida in substituiranih vinil etrov) reakcijski napad preferenčno ekso ali endo. Rezultate, dobljene z računsko metodo PM6, sem primerjal z eksperimentalnimi podatki, vključno z že objavljenimi v literaturi. 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. |
