CC BY-ND-NC 4.0 · Synthesis 2019; 51(05): 1021-1036
DOI: 10.1055/s-0037-1611636
short review
Copyright with the author

Conformational Dynamics in Asymmetric Catalysis: Is Catalyst Flexibility a Design Element?

Jennifer M. Crawford
,
Matthew S. Sigman*
Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, USA   Email: sigman@chem.utah.edu
› Author Affiliations
J.M.C. acknowledges the support of the NSF Graduate Research Fellowship Program. M.S.S. thanks the NIH (1 R01 GM121383) for supporting this work.
Further Information

Publication History

Received: 23 November 2018

Accepted: 28 November 2018

Publication Date:
08 January 2019 (online)


Published as part of the 50 Years SYNTHESIS – Golden Anniversary Issue

Abstract

Traditionally, highly selective low molecular weight catalysts have been designed to contain rigidifying structural elements. As a result, many proposed stereochemical models rely on steric repulsion for explaining the observed selectivity. Recently, as is the case for enzymatic systems, it has become apparent that some flexibility can be beneficial for imparting selectivity. Dynamic catalysts can reorganize to maximize attractive non-covalent interactions that stabilize the favored diastereomeric transition state, while minimizing repulsive non-covalent interactions for enhanced selectivity. This short review discusses catalyst conformational dynamics and how these effects have proven beneficial for a variety of catalyst classes, including tropos ligands, cinchona alkaloids, hydrogen-bond donating catalysts, and peptides.

1 Introduction

2 Tropos Ligands

3 Cinchona Alkaloids

4 Hydrogen-Bond Donating Catalysts

5 Peptide Catalysts

6 Conclusion