Catalysis by electrons and holes: formal potential scales and preparative organic electrochemistry
The present review surveys current chemical understanding of catalysis by addition and removal of an electron. As an overarching theme of this type of catalysis, we introduce the role of redox scales in oxidation and reduction reactions as a direct analogue of pK_a scales in acid/base catalysis. Each scale is helpful in determining the type of reactivity to be expected. In addition, we describe several means of generating electrons and holes via chemical reactions, plasmonic resonance, radiolytic, photochemical and electrochemical methods. We specifically draw parallels between the now well-established fields of photoredox catalysis and chemical opportunities made available by electrochemical methods. We highlight accessible potential ranges for a series of electrochemical solvents and provide a discussion on experimental design, pitfalls and some remaining challenges in preparative organic electrochemistry.
© 2015 the Partner Organisations. Received 5th March 2015, Accepted 15th April 2015. First published online 07 May 2015. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. JLG would like to thank SDSU for startup funds. We thank Dr Charles McCrory, Dr John Gregoire, Dr James Blakemore, Dr Kevin Oberg, Mr Chris Nalbandian, Dr Corinne Allen and Professors Donna Blackmond, Carl Koval, Keary Engle, Phil Baran, Robert Crabtree, Seth Herzon, Jonas Peters, T. Don Tilley, Clifford Kubiak and Nathan Lewis for insightful discussions.
Published - c5qo00075k.pdf