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V uvodnem delu diplomskega dela so predstavljene Diels–Alderjeve reakcije, njihova stereokemija in regioselektivnost. Opisane so tudi značilnosti sodelujočih dienov in dienofilov. Večji poudarek je namenjen 2H-piran-2-onom, ki predstavljajo zanimive diene za [4+2] cikloadicije. Na kratko so predstavljene tudi teoretične študije mehanizma Diels–Alderjevih reakcij. Večji del teoretičnega uvoda pokriva predstavitev organokatalize, klasifikacija le-te na kovalentno in nekovalentno katalizo in predstavitev predstavnikov posamezne organokatalize. Narejen je tudi manjši oris uporabe predstavljene katalize pri Diels–Alderjevih reakcijah, kjer 2H-piran-2-oni igrajo vlogo diena. Eksperimentalni del se navezuje na pripravo substituiranih 3-benzoilamino-2H-piran-2-onov, odščito aminske skupine pod kislimi pogoji ter uvedbo nove zaščitne skupine s pomočjo ustreznega kislinskega klorida. Izvedeni sta bili tudi Diels–Alderjevi reakciji z izbranim derivatom 2H-piran-2-ona in maleinanhidridom pod refluksom ter z obsevanjem z mikrovalovi. The Diploma work presents Diels–Alder reactions, their stereochemistry and regioselectivity. It covers the properties of typically used dienes and dienophiles. 2H-Pyran-2-ones are reviewed in detail, as they present interesting dienes in [4+2] cycloadditions. The theoretical studies of Diels–Alder reaction mechanism are also briefly addressed. A large part of the theoretical introduction is comprised of a review of organocatalysis. Covalent and non-covalent catalysis and the representatives of organocatalytic methods are introduced. A brief description of organocatalytic Diels–Alder reactions of 2H-pyran-2-ones is presented. In the experimental work, the synthesis of 3-benzoylamino-2H-pyran-2-ones, selective deprotection of the 3-amino group under acid conditions and an addition of a new protective group with a corresponding acyl chloride is presented. It is followed by two Diels–Alder reactions using a derivate of 2H-pyran-2-one and maleic anhydride. The described [4+2] cycloadditions were investigated under reflux and microwave irradiation. |
