title: NHC-Organocatalyzed CAr-O Bond Cleavage: Mild Access to 2-Hydroxybenzophenones.
abstract: A Truce-Smiles rearrangement of acyl-anion equivalents generated by N-heterocyclic carbene (NHC) catalysis has been achieved. The developed method includes CAr-O, CAr-S, or CAr-N bond cleavage for the formation of a CAr-C bond and enables access to 2-hydroxybenzophenones, an important structural motif that is present in several bioactive natural products. By utilizing this procedure, the alkaloid taxilamine was synthesized in three steps. DFT calculations and control experiments support a classical SNAr mechanism with a catalyst-bound Meisenheimer-type intermediate. The method features mild reaction conditions, excellent functional-group tolerance, and a broad substrate scope, including various classes of (hetero)arenes.
authors.affiliation: Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Janssen-Müller
authors.affiliation: Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany.
authors.forename: Santanu
authors.initials: S
authors.lastname: Singha
authors.affiliation: Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany.
authors.forename: Fabian
authors.initials: F
authors.lastname: Lied
authors.affiliation: Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany.
authors.forename: Karin
authors.initials: K
authors.lastname: Gottschalk
authors.affiliation: Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany.
authors.forename: Frank
authors.identifier: 0000-0002-0648-956X
authors.initials: F
authors.lastname: Glorius
keywords: aromatic substitution; carbenes; natural products; organocatalysis; rearrangement