Reductive activation of C—Sand C—O bonds: an electrosyntheticand computational study
Time: Fri 2026-02-20 10.00
Location: F3, Lindstedtvägen 26
Language: English
Subject area: Chemistry
Doctoral student: Julius Kuzmin , Organisk kemi
Opponent: Doktor Giacomo Crisenza, University of Manchester, England
Supervisor: Universitetslektor Helena Lundberg Ankner, Organisk kemi; Universitetslektor Markus D. Kärkäs, Organisk kemi; Professor Mårten Ahlquist, Teoretisk kemi och biologi
QC 20260129
Abstract
Organic electrosynthesis uses electricity as the “reagent” to drive redox reactionsinstead of relying on more traditional oxidants or reductants. Because electronsare supplied directly from an electrode, reactions can often be run underrelatively mild conditions and with less chemical waste. In this thesis,electrochemical methods are developed to target carbon-sulfur (C-S) bonds incommon sulfur-containing compounds of thioethers, thioacetals, disulfides, andthiols, and, in an analogous way, carbon-oxygen (C-O) bonds in esters.A major part of the work shows how aryl-alkyl thioethers can act as an alkylsource under electroreductive conditions. When electrolyzed the C(sp³)-S bondis cleaved selectively to form carbon centered radical, which can cross over to acarbanion. These intermediates can be converted into alkanes, or react withcarbon dioxide to form carboxylic acids, or add to electron-poor alkenes in aGiese-type reaction. Using the same activation concept, the thesis alsointroduces an electrochemical route to valuable alkylboronic esters by couplingthe carbanion with a boron reagent. Notably, this borylation strategy worksacross several classes of sulfur-containing motifs.Beyond developing new reactions, the thesis also addresses a practical challengein electrosynthesis. Many net-reductive electrochemical methods still rely onsacrificial metal anodes that are consumed during the reaction. Here,borohydride oxidation with inert anodes is evaluated as an alternative counterreaction across several net-reductive protocols, steering toward a moreoperationally convenient electrolysis setup.Finally, the thesis explores the electrochemical deoxygenation Markó-Lamreaction of esters using a computational approach. By mapping how variousdescriptors influence the C-O bond breaking step, the study connectsmeasurable properties such as reduction potentials with reaction barriers.