Electrode‐Potential‐Driven Dissociation of N‐Heterocycle/BF3 Adducts: A Possible Manifestation of the Electro‐Inductive Effect

• Published in: Angewandte Chemie International Edition Vol. 62; no. 24; pp. e202304218 - n/a
• Main Authors: Hossain, Md. Sazzad, Romo, Adolfo I. B., Putnam, Seth T., Dawlaty, Jahan, Augustyn, Veronica, Rodríguez‐López, Joaquín
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 12.06.2023
• Edition: International ed. in English
• Subjects: Adduct; Adducts; Chemical reactions; Electro-Inductive Effect; Electrochemistry; Electrode polarization; Electrodes; Electron transfer; Electronic structure; Electrostatic properties; Electrostatics; Fluorescence; Fluorescence spectroscopy; Perturbation; Redox potential; Scanning Electrochemical Microscopy
• DOI: 10.1002/anie.202304218
• ISSN: 1433-7851

Recently, non‐Faradaic effects were used to modify the electronic structure and reactivity of electrode‐bound species. We hypothesize that these electrostatic perturbations could influence the chemical reactivity of electrolyte species near an electrode in the absence of Faradaic electron transfer. A prime example of non‐Faradaic effects is acid‐base dissociation near an interface. Here, we probed the near‐electrode dissociation of N‐heterocycle‐BF3 Lewis adducts upon electrode polarization, well outside of the redox potential window of the adducts. Using scanning electrochemical microscopy and confocal fluorescence spectroscopy, we detected a potential‐dependent depletion of the adduct near the electrode. We propose an electro‐inductive effect where a more positive potential leads to electron withdrawal on the N‐heterocycle. This study takes a step forward in the use of electrostatics at electrochemical interfaces for field‐driven electrocatalytic and electro‐synthetic processes. In a non‐redox fashion, applied potential dissociates acid‐base N‐heterocycle‐BF3 couples in the diffusion layer near an electrode. This effect was probed using scanning electrochemical microscopy and confocal fluorescence spectroscopy.