S02 Conversion to Sulfones: Development and Mechanistic Insights of a Sulfonylative Hiyama Cross-Coupling Reaction

Aurélien Adenot (1) , Joëlle Char (1) , Niklas von Wolff (1) , Guillaume Lefèvre (1) , Thibault Cantat (1)

1 LCMCE - Laboratoire de Chimie Moléculaire et de Catalyse pour l'Energie (ex LCCEF)

Due to distinctive structural and electronic features, sulfones have attracted a particular attention over the past few decades, making' it a widespread functional group.1 Present in many contemporary pharmaceuticals and agrochemicals, they are also used as essential intermediates in organic synthesis. Therefore, numerous methodologies have been developed for their preparation. 1 However, the most common methods (see Scheme below) suffer from significant limitations with harsh reaction conditions or regioselectivity issues. Recently, the insertion of a molecule of sulfur dioxide between two partners was investigated and reactions involving organomagnesium,2a organozinc 2b and organoboron 2c compounds were reported. As regards the use of organosilanes to produce sulfones from S02 or S02 surrogates, developed routes are limited to the formation of an intermediate sulfinate anion that· undergoes S-alkylation and therefore to sp3-hybridized electrophiles only.3 Herein we report the first Hiyama cross-coupling, enabling the synthesis of sulfones in a direct single-step from organosilanes, S02 and sp2-hybridized electrophiles. Different mechanistic pathways were envisaged and discussed both from an experimental and theoretical standpoint.

Domaines: Matériaux

Aurélien Adenot, Joëlle Char, Niklas von Wolff, Guillaume Lefèvre, Thibault Cantat. S02 Conversion to Sulfones: Development and Mechanistic Insights of a Sulfonylative Hiyama Cross-Coupling Reaction. ISySyCat 2019, Sep 2019, Evora, Portugal. ⟨cea-02329649⟩