In this diploma I present different types of substrate activation commonly applied in the field of asymmetric noncovalent organocatalysis. These methods are categorized into Brønsted acid catalyzed reactions, hydrogen-bond catalysis and ion-pairing reactions. My aim was to thoroughly research various BINOL-phosphate derived Brønsted acids as they are most commonly used in Brønsted acid catalyzed reactions. Catalysts can be used to activate either the electrophile or the nucleophile in several different ways, often referred to as mono-, dual- or bifunctional activation. All of these methods were theoretically studied. Some common catalysts rely on hydrogen bond formation to direct the reaction along the desired pathway. They are referred to as Takemoto-type catalysts, some of which include an additional functional group that enables the formation of an additional hydrogen bond, thus potentially increasing stereoselectivity. Squaramides can also be applied in this manner. Because quarternary ammonium cations have the ability to form ion-pairs with charged intermediates or substrates, they are often used in organocatalysis. I presented different reaction mechanisms and studied what enables them to achieve the desired effect.
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