Host-guest induced electron transfer triggers radical-cation catalysis

Spicer, R. L., Stergiou, A., Young, T. A., Duarte, F., Symes, M. D. and Lusby, P. J. (2020) Host-guest induced electron transfer triggers radical-cation catalysis. Journal of the American Chemical Society, (doi: 10.1021/jacs.9b11273) (PMID:31935091)

Abstract

Modifying the reactivity of substrates by encapsulation is a fundamental principle of capsule catalysis. Here we show an alternative strategy, wherein catalytic activation of otherwise inactive quinone “co-factors” by a simple Pd2L4 capsule pro-motes a range of bulk-phase, radical-cation cycloadditions. Solution electron transfer experiments and cyclic voltammetry show the cage anodically shifts the redox potential of the encapsulated quinone by a significant 1 V. Moreover, the capsule also protects the reduced semiquinone from protonation, thus transforming the role of quinones from stoichiometric oxidants into catalytic single electron acceptors. We envisage that the host-guest induced release of an “electron hole” will translate to various forms of non-encapsulated catalysis that involve other difficult to handle, highly reactive species.

• Item Type: Articles
• Additional Information: The authors also acknowledge the following EPSRC Centers for Doctoral training: Critical Resource Catalysis (CRITICAT, EP/L016419/1) for a studentship for RLS, and Theory and Modelling in Chemical Sciences (EP/L015722/1) for a studentship to TAY generously supported by AWE.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Stergiou, Mr Athanasios and Symes, Professor Mark
• Authors: Spicer, R. L., Stergiou, A., Young, T. A., Duarte, F., Symes, M. D., and Lusby, P. J.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Journal of the American Chemical Society
• Publisher: American Chemical Society
• ISSN: 0002-7863
• ISSN (Online): 1520-5126
• Published Online: 14 January 2020
• Copyright Holders: Copyright © 2020 American Chemical Society
• First Published: First published in Journal of the American Chemical Society 142(5):2134-2139
• Publisher Policy: Reproduced in accordance with the publisher copyright policy

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
173495		Driving energetically uphill processes using metal-ligand coordination complexes	Mark Symes	The Royal Society (ROYSOC)	UF150104	Chemistry