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Published on: November 30, 2022
Fluorination of arylboronic esters enabled by bismuth redox catalysis
Oriol Planas1, Feng Wang1, Markus Leutzsch1
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany.
Abstract:
Bismuth catalysis has traditionally relied on the Lewis acidic properties of the element in a fixed oxidation state. In this paper, we report a series of bismuth complexes that can undergo oxidative addition, reductive elimination, and transmetallation in a manner akin to transition metals. Rational ligand optimization featuring a sulfoximine moiety produced an active catalyst for the fluorination of aryl boronic esters through a bismuth (III)/bismuth (V) redox cycle. Crystallographic characterization of the different bismuth species involved, together with a mechanistic investigation of the carbon-fluorine bond-forming event, identified the crucial features that were combined to implement the full catalytic cycle.
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