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.
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