title: Ethenesulfonyl Fluoride: The Most Perfect Michael Acceptor Ever Found?
abstract: The kinetics of the reactions of ethenesulfonyl fluoride (ESF) with sulfonium and pyridinium ylides were measured photometrically to determine the electrophilicity parameter of ESF according to the correlation lg k20 °C =sN (N+E). With E=-12.09, ESF is among the strongest Michael acceptors in our comprehensive electrophilicity scale, which explains its excellent performance in reactions with many nucleophiles. Its predicted usability as a reagent in electrophilic aromatic substitutions with electron-rich arenes was confirmed by uncatalyzed reactions with alkyl-substituted pyrroles.
authors.affiliation: Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, Haus F, 81377, München, Germany.
authors.forename: Quan
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, Haus F, 81377, München, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Mayer
authors.affiliation: Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, Haus F, 81377, München, Germany. Herbert.Mayr@cup.uni-muenchen.de.
authors.forename: Herbert
authors.identifier: 0000-0003-0768-5199
authors.initials: H
authors.lastname: Mayr
keywords: electrophilic aromatic substitution; electrophilicity; linear free-energy relationships; reaction kinetics; ylides