- Akamatsu, M.; Sakai, N.; Matile, S. “Electric-Field-Assisted Anion-π Catalysis” J. Am. Chem. Soc. 2017, 139, 6558-6561
This report focuses on the remote control of anion−π catalysis by electric fields. We have synthesized and immobilized anion−π catalysts to explore the addition reaction of malonic acid half thioesters to enolate acceptors on conductive indium tin oxide surfaces. Exposed to increasing electric fields, anion−π catalysts show an increase in activity and an inversion of selectivity. These changes originate from a more than 100-fold rate enhancement of the disfavored enolate addition reaction that coincides with an increase in selectivity of transition-state recognition by up to −14.8 kJ mol–1. The addition of nitrate with strong π affinity nullified (IC50 = 2.2 mM) the responsiveness of anion−π catalysts to electric fields. These results support that the polarization of the π-acidic naphthalenediimide surface in anion−π catalysts with electric fields increases the recognition of anionic intermediates and transition states on this polarized π surface, that is, the existence and relevance of electric-field-assisted anion−π catalysis.
DOI: 10.1021/jacs.7b02421
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