Bénédicte Delouvrié

The Chemistry of C2‐Symmetric Bis(sulfoxides): A New Approach in Asymmetric Synthesis

The preparation of various racemic or enantiopure C2-symmetric bis(sulfoxides) has been developed over the last decades. Numerous applications in organic synthesis (anionic condensation, cycloadditions) as well as in coordination chemistry have been worked out. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

A new radical synthesis of allenes

Abstract The unprecedented radical β-elimination of vinylsulfoxides opens a new access to functionalized di- and trisubstituted allenes. The radical precursors are obtained in two steps from a carbonyl derivative and a vinylsulfoxide. The radical translocation trick can also be used to trigger the β-elimination of the sulfinyl radical.

Radical Cyclization/β-Elimination Tandem Reactions: Enantiopure Sulfoxides as Temporary Chiral Auxiliaries

Alkylidene-substituted cyclopentane derivatives are formed in high enantiomeric purity by the reaction shown below. A highly diastereoselective radical cyclization is followed by elimination of a β-sulfinyl radical. Interestingly, the addition of the Lewis acid methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide) (MAD) totally reverses the stereochemical outcome of the reaction. E=CO2 Me.

Radical β-Elimination of a Sulfinyl Group to Afford Allenes

An unprecedented radical β-elimination of vinyl sulfoxides has opened a new route to functionalized allenes. The radical precursors were obtained in two steps from a carbonyl derivative and a vinyl sulfoxide. The radical translocation stratagem could also be used to trigger the β-elimination of the sulfinyl radical. Variation of the nature of the sulfur group on a common precursor gave no allene with the thio, sulfonyl, and iminosulfinyl moieties, in contrast to the analogous vinyl sulfoxide and vinylsulfimide precursors. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

Reactivity of the lithium anion of the (S,S)-bis-p-tolylsulfinyl methane. A versatile synthesis of enantiopure alkylidene 1,1-bis-p-tolylsulfoxides

We describe herein a new synthesis of enantiopure alkylidene 1,1-bis-p-tolyl-sulfoxides (5), based on a two-steps sequence. The first one involves the alkylation of the lithium anion of the (S,S)-bis-p-tolylsulfinylmethane (1) with aldehydes. The second one consists in a mild dehydration of the sulfinyl alcohols 3 and 4 with the morpho CDI reagent. Some features (reactivity, diastereoselectivity) of the alkylation reaction are discussed.

New developments in radical chemistry. Applications to total synthesis and asymmetric processes

This article reviews our contribution in the field of radical synthetic chemistry, focusing on cascades relying on the use of propargylic BMDMS ethers and asymmetric synthesis using enantiopure vinylsulfoxides.

Conjugate Additions to Alkylidene Bis(Sulfoxides)

A general study on the conjugate addition of anionic nucleophiles to alkylidene bis(sulfoxides) is presented. Alkoxides gave high yielding and diastereoselective addition reactions, which could be influenced by solvents and the counteranion. Azides provided an interesting entry into sulfinyl-substituted triazoles. Organometallics, mainly copper reagents, proved also to be valuable nucleophiles, and complete inversion of the stereoselectivity was achieved in the addition reaction with the latter. Modelizations provide a rationale for the observed diastereoselectivity.

New Advances in Bis(Sulfoxides) Chemistry

Abstract The chemistry of bis(sulfoxides) is discussed from two starting materials, (Ss,Ss)-bis-p-tolylsulfinylmethane and (Ss,Ss)-bis-p-tolylsulfinyl alkylidenes. Reactions presented include Michael additions, ionic-radical crossover processes and coordination complexes formations. GRAPHICAL ABSTRACT

Radikalcyclisierungs/β‐Eliminierungs‐Dominoreaktionen: enantiomerenreine Sulfoxide als temporäre chirale Auxiliare

Alkylidensubstituierte Cyclopentanderivate entstehen nach der unten dargestellten Reaktion in hoher Enantiomerenreinheit. Zunachst findet eine hochdiastereoselektive Radikalcyclisierung statt, an die sich die Eliminierung des β-Sulfinylradikals anschliest. Interessanterweise wird durch Zugabe der Lewis-Saure Methylaluminiumbis(2,6-di-tert-butyl-4-methylphenoxid) (MAD) der stereochemische Verlauf der Reaktion vollstandig umgekehrt. E=CO2Me.