Stephen Fletcher

Prof Stephen Fletcher

Professor Stephen Fletcher

Professor of Chemistry

 

 

Research Interests

My research group's interests are in the areas of synthesis, catalysis and the design of molecular systems. We are developing new catalytic asymmetric carbon-carbon bond forming reactions to rapidly access complex molecules from simple molecules and then apply these methods to the construction of important targets like natural products and clinically used drugs. We are also working to uncover how some of the most basic functions of living systems can be observed in purely synthetic systems with the long-term goal of understanding what is different about living and non-living matter and how to construct new molecular machines. 

Asymmetric cross-coupling reactions

My group has developed a series of Cu- and Rh-catalyzed asymmetric reactions that form C-C bonds under easily accessible conditions. We are particularly interested in developing new catalytic asymmetric variations of widely used cross-coupling reactions like Suzuki-Miyaura coupling that will allow rapid access to complex three dimensional architectures with high diastereo- and enantiomeric control. As well as developing methods we perform mechanistic studies to understand how these transformations work, and have developed an approach to understanding the sources of asymmetric induction so that we can design new ligands and catalysts. We have applied these methods to the synthesis of clinically used drugs and natural products such as fulvestrant, tafluprost, niraparib and the taxol core.

Self-replicating systems

We are investigating different avenues to learn how small molecules may self-replicate, and have developed new systems involving self-replicating micelles and vesicles. The mechanisms of these processes are very important to us and we use kinetics and other mechanistic studies to understand how these systems can be controlled. We have made many intriguing discoveries during this research, for example how to couple self-reproduction to secondary processes and how ‘selection’ and ‘evolution’ may occur within lipid replicators (i.e. without nucleotides or other biologically based template mechanisms) and we are currently working to understand how lipid self-replication can be used to drive novel macromolecular and microscopic phenomena.

Molecular machines and how to transmit information and work across length scales

We have previously performed structure-activity relationship studies of how to control photoisomerization in dynamic molecular systems, built systems capable of performing macroscopic work, and learned how to control self-replication in supramolecular systems. Our current aims are to understand how molecular signals can transmit information, or be use to drive processes at different length scales. We are especially interested in how chirality can be amplified to control the geometry and properties of nanoscale materials. We also aim to understand how dynamic supramolecular and microscale systems may be constructed, maintained and controlled using the chemistry of small molecules.
 

Biography

Stephen Fletcher studied chemistry at Mount Allison University in Canada before obtaining a PhD from the University of Alberta working with Derrick Clive in organic synthesis. He was a NSERC of Canada Postdoctoral Fellow in Ben Feringa’s group at the University of Groningen in the Netherlands, before working with Jonathan Clayden at the University of Manchester.

He moved to Oxford to start independent research in 2009 as an EPSRC Career Acceleration Fellow, and subsequently became a tutorial Fellow at Keble College and was promoted to Full Professor in 2018. He has a variety of research interests including asymmetric catalysis and complex dynamic systems – and been generously supported by the EPSRC and an ERC Consolidator Grant (Autocatalysis: a bottom-up approach to understanding the origins of life). Award include the 2023 Royal Society of Chemistry, Merck Sharp & Dohme Prize.

Publications

Contact

stephen.fletcher@chem.ox.ac.uk
01865 275642

Research group

Fletcher Research Group

College

Keble College