Ph.D. Thesis_AS_Publishing version for IRC_12 ... - Jacobs University

Chapter 1
1.5 Research Goals: bifunctional based asymmetric Michael additions
1.5.1 Primary-tertiary diamine for addition of cyclopentanone to nitroolefins
Over the past few years, a variety of classes of organocatalysts has been developed for different
asymmetric reactions. Aminocatalysis represents a prevailing class of these catalysts. Chiral
secondary amines are by far the most intensively studied. By contrast, primary amine catalysts
were ignored. Despite the reasons, primary amine catalysts recently emerged as a new tool for
asymmetric reactions. On the other hand, some substrates (e.g. cyclopentanone, α-substituted
aldehydes) in asymmetric Michael addition are still an open challenge for new researchers. My
goal was the synthesis of bifunctional organocatalsyts containing primary amine and to explore
their applications in asymmetric Michael addition of ketones (cyclopentanone) and aldehydes to
nitroolefins.
1.5.2 Non-covalent catalysts for addition of α-substituted aldehydes to maleimides
Asymmetric Michael addition to maleimides leads to the products, called succinimides. These
products and their reduced forms (chiral pyrrolidines and δ-lactams) are important building
blocks for drugs and natural products. Additions of α-branched aldehydes to maleimides give
more complex succinimides products with contiguous quaternary-tertiary stereogenic carbons.
These types of Michael additions are uncommon and not fully explored. My goal was to design
bifunctional catalysts which would overcome the reported limitations to access these tough α-
succinimide products.
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