Abstract
Most chemical reactions proceed via charged intermediates or transition states. Such "polar reactions" can be influenced by the counterion, especially if conducted in organic solvents, where ion pairs are inefficiently separated by the solvent. Although asymmetric catalytic transformations involving anionic intermediates with chiral, cationic catalysts have been realized, analogous versions of inverted polarity with reasonable enantioselectivity, despite attempts, only recently became a reality. In this talk, the speaker will present the development of this concept, which is termed asymmetric counteranion-directed catalysis (ACDC) and illustrate its generality with examples from organocatalysis, transition metal catalysis and Lewis acid catalysis.
About the speaker
Prof Benjamin List received his PhD from the Goethe University Frankfurt in 1997. He was postdoc and later Assistant Professor at the Scripps Research Institute. He joined the Max Planck Institute for Coal Research in 2003, and is currently Managing Director of the Institute.
Prof List's research focuses on organic synthesis and catalysis. He has contributed and pioneered fundamental concepts in organocatalysis including aminocatalysis, enamine catalysis, and asymmetric counteranion-directed catalysis (ACDC). After his discovery of the proline-catalyzed direct asymmetric intermolecular aldol reaction in 2000, his research group has introduced the first proline-catalyzed asymmetric Mannich reaction, novel Michael additions, a-aminations, enol-exo-aldolizations, and aldehyde a-alkylations. His collaborative efforts have provided a clearer mechanistic understanding of enamine catalysis and established the basis for the design of new reactions and catalysts. His latest work deals with chiral anions in asymmetric catalysis. His general concept of ACDC has recently found widespread use in organocatalysis, transition metal catalysis, and Lewis acid catalysis.
Prof List received numerous awards including the Cope Scholar Award, the Horst-Pracejus-Preis and the Mukaiyama Award, the Otto-Sayer-Prize, the Cari-Duisberg-Memorial Award, and the Degussa Prize for Chiral Chemistry, etc.
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