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Lecture

Iminium Catalysis: Asymmetric Transformations

In course

CH-435: Asymmetric catalysis for fine chemicals synthesis

The asymmetric synthesis of fine chemicals is a research topic of growing importance for the synthesis of modern materials, drugs and agrochemicals. In this lecture, the concepts of asymmetric catalysis for fine chemical synthesis are introduced. ...

Description

This lecture covers the use of iminium catalysis in asymmetric transformations, focusing on examples such as Diels-Alder reactions, conjugate additions, and conjugate reductions. The slides detail the mechanisms, selectivity models, and key reactions developed by MacMillan, Northrup, and others.

Instructor

Jérôme Waser

Jérôme Waser biography and CV's are available on the following website: http://lcso.epfl.ch/waser

Official source

Related concepts (32)

Enantioselective synthesis

Enantioselective synthesis, also called asymmetric synthesis, is a form of chemical synthesis. It is defined by IUPAC as "a chemical reaction (or reaction sequence) in which one or more new elements of chirality are formed in a substrate molecule and which produces the stereoisomeric (enantiomeric or diastereomeric) products in unequal amounts." Put more simply: it is the synthesis of a compound by a method that favors the formation of a specific enantiomer or diastereomer.

Catalysis

Catalysis (kəˈtæləsɪs) is the process of change in rate of a chemical reaction by adding a substance known as a catalyst (ˈkætəlɪst). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst.

Asymmetric induction

Asymmetric induction (also enantioinduction) describes the preferential formation in a chemical reaction of one enantiomer or diastereoisomer over the other as a result of the influence of a chiral feature present in the substrate, reagent, catalyst or environment. Asymmetric induction is a key element in asymmetric synthesis. Asymmetric induction was introduced by Hermann Emil Fischer based on his work on carbohydrates. Several types of induction exist.

Michael addition reaction

In organic chemistry, the Michael reaction or Michael 1,4 addition is a reaction between a Michael donor (an enolate or other nucleophile) and a Michael acceptor (usually an α,β-unsaturated carbonyl) to produce a Michael adduct by creating a carbon-carbon bond at the acceptor's β-carbon. It belongs to the larger class of conjugate additions and is widely used for the mild formation of carbon-carbon bonds.

Conjugate transpose

In mathematics, the conjugate transpose, also known as the Hermitian transpose, of an complex matrix is an matrix obtained by transposing and applying complex conjugate on each entry (the complex conjugate of being , for real numbers and ). It is often denoted as or or and very commonly in physics as . For real matrices, the conjugate transpose is just the transpose, . The conjugate transpose of an matrix is formally defined by where the subscript denotes the -th entry, for and , and the overbar denotes a scalar complex conjugate.

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Catalytic Asymmetric Reactions in Organic Chemistry

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Catalytic Reactions: Mannich and Strecker Pathways

Explores catalytic Mannich and Strecker reactions, Aza-Friedel Craft reaction, and carbonyl reaction extensions, including Diels Alder cycloaddition.

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Related concepts (32)

Enantioselective synthesis

Catalysis

Asymmetric induction

Michael addition reaction

Conjugate transpose