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L’utilisation de méthodologies de synthèse toujours plus performantes et respectueuses de l’environnement est un axe de recherche majeur de la chimie moderne. L’apport de la catalyse, avec l’utilisation de superacides de Lewis, a permis d’améliorer de nombreux processus synthétiques. Nous avons pu développer dans ce manuscrit des réactions de cycloisomérisation de type réaction de Friedel-Crafts qui donnent accès à un ensemble de structures polycycliques intéressantes avec de bons rendements et sélectivités. L’utilisation d’une quantité catalytique, entre 1 et 10 mol% de Bi(OTf)3, permet l’activation d’oléfines et d’allènes non activés ainsi que de systèmes 1,3-diéniques. Ce type de méthodologie, à économie d’atomes maximale, a permis de limiter la formation de sous-produits, le catalyseur pouvant être recyclé et réutilisé sans perte d’activité. Des approches intra- et intermoléculaires, des réactions cascades et tandems ainsi qu’une étude mécanistique ont été effectuées afin de mieux comprendre la réactivité et ses limitations, et ainsi atteindre une plus large gamme de structures. Les méthodologies développées ont été appliquées au domaine des arômes et parfums pour la synthèse d’analogues de la Calone 1951®, de chromanes, d’indanes et de tétralines fonctionnalisés, posant les bases de travaux futurs pour une meilleur compréhension des relations structures-odeursEfficient and ecofriendly synthetic methodologies have always constituted an important area of research in modern organic chemistry. Lewis superacid catalysis has contributed in the improvement of many synthetic processes. We have developed some cycloisomerization reactions including Friedel-Crafts type reaction, giving access to a set of interesting polycyclic structures with good yields and selectivities. The use of a catalytic amount of Bi(OTf)3 (1 to 10 mol%), has allowed the activation of olefins, non-activated allenes and of 1,3-dienic systems. This atom economy methodology can prevent the formation of by-products and the catalyst can be recycled without loss of activity. Intra- and intermolecular approaches, tandem and cascades reactions, as well as mechanistic studies were conducted to enable a better understanding of the reactivity and its limitations to reach a wider range of structures. The developed methodologies were applied to the field of flavors and fragrances in the synthesis of Calone 1951® analogues, and for the preparation of chromans, indanes and tetralins type functionalized structures, for a better understanding of the structure/odor relationship

Formation de composés polycycliques par activation de doubles liaisons : approche catalytique intra et intermoléculaire de réactions de type Friedel-Crafts : applications au domaine des arômes et parfums

Efficient and ecofriendly synthetic methodologies have always constituted an important area of research in modern organic chemistry. Lewis superacid catalysis has contributed in the improvement of many synthetic processes. We have developed some cycloisomerization reactions including Friedel-Crafts type reaction, giving access to a set of interesting polycyclic structures with good yields and selectivities. The use of a catalytic amount of Bi(OTf)3 (1 to 10 mol%), has allowed the activation of olefins, non-activated allenes and of 1,3-dienic systems. This atom economy methodology can prevent the formation of by-products and the catalyst can be recycled without loss of activity. Intra- and intermolecular approaches, tandem and cascades reactions, as well as mechanistic studies were conducted to enable a better understanding of the reactivity and its limitations to reach a wider range of structures. The developed methodologies were applied to the field of flavors and fragrances in the synthesis of Calone 1951® analogues, and for the preparation of chromans, indanes and tetralins type functionalized structures, for a better understanding of the structure/odor relationship.L’utilisation de méthodologies de synthèse toujours plus performantes et respectueuses de l’environnement est un axe de recherche majeur de la chimie moderne. L’apport de la catalyse, avec l’utilisation de superacides de Lewis, a permis d’améliorer de nombreux processus synthétiques. Nous avons pu développer dans ce manuscrit des réactions de cycloisomérisation de type réaction de Friedel-Crafts qui donnent accès à un ensemble de structures polycycliques intéressantes avec de bons rendements et sélectivités. L’utilisation d’une quantité catalytique, entre 1 et 10 mol% de Bi(OTf)3, permet l’activation d’oléfines et d’allènes non activés ainsi que de systèmes 1,3-diéniques. Ce type de méthodologie, à économie d’atomes maximale, a permis de limiter la formation de sous-produits, le catalyseur pouvant être recyclé et réutilisé sans perte d’activité. Des approches intra- et intermoléculaires, des réactions cascades et tandems ainsi qu’une étude mécanistique ont été effectuées afin de mieux comprendre la réactivité et ses limitations, et ainsi atteindre une plus large gamme de structures. Les méthodologies développées ont été appliquées au domaine des arômes et parfums pour la synthèse d’analogues de la Calone 1951®, de chromanes, d’indanes et de tétralines fonctionnalisés, posant les bases de travaux futurs pour une meilleur compréhension des relations structures-odeur

Formation de composés polycycliques par activation de doubles liaisons (applications au domaine des arômes et parfums)

L utilisation de méthodologies de synthèse toujours plus performantes et respectueuses de l environnement est un axe de recherche majeur de la chimie moderne. L apport de la catalyse, avec l utilisation de superacides de Lewis, a permis d améliorer de nombreux processus synthétiques. Nous avons pu développer dans ce manuscrit des réactions de cycloisomérisation de type réaction de Friedel-Crafts qui donnent accès à un ensemble de structures polycycliques intéressantes avec de bons rendements et sélectivités. L utilisation d une quantité catalytique, entre 1 et 10 mol% de Bi(OTf)3, permet l activation d oléfines et d allènes non activés ainsi que de systèmes 1,3-diéniques. Ce type de méthodologie, à économie d atomes maximale, a permis de limiter la formation de sous-produits, le catalyseur pouvant être recyclé et réutilisé sans perte d activité. Des approches intra- et intermoléculaires, des réactions cascades et tandems ainsi qu une étude mécanistique ont été effectuées afin de mieux comprendre la réactivité et ses limitations, et ainsi atteindre une plus large gamme de structures. Les méthodologies développées ont été appliquées au domaine des arômes et parfums pour la synthèse d analogues de la Calone 1951®, de chromanes, d indanes et de tétralines fonctionnalisés, posant les bases de travaux futurs pour une meilleur compréhension des relations structures-odeursEfficient and ecofriendly synthetic methodologies have always constituted an important area of research in modern organic chemistry. Lewis superacid catalysis has contributed in the improvement of many synthetic processes. We have developed some cycloisomerization reactions including Friedel-Crafts type reaction, giving access to a set of interesting polycyclic structures with good yields and selectivities. The use of a catalytic amount of Bi(OTf)3 (1 to 10 mol%), has allowed the activation of olefins, non-activated allenes and of 1,3-dienic systems. This atom economy methodology can prevent the formation of by-products and the catalyst can be recycled without loss of activity. Intra- and intermolecular approaches, tandem and cascades reactions, as well as mechanistic studies were conducted to enable a better understanding of the reactivity and its limitations to reach a wider range of structures. The developed methodologies were applied to the field of flavors and fragrances in the synthesis of Calone 1951® analogues, and for the preparation of chromans, indanes and tetralins type functionalized structures, for a better understanding of the structure/odor relationship.NICE-Bibliotheque electronique (060889901) / SudocSudocFranceF

ScCO2 assisted preparation of supported metal NPs. Application to catalyst design.

Designing and developing materials with specific properties are nowadays important tasks. These could be achieved by choosing the adequate conditions, from a myriad of possibilities, being aware that slight changes in the preparation method could have major impact on the final material. With the work presented here, we are showing that kinetically controlled surface nano-structuring (NPs formation and deposition over solid supports) in scCO2 is a versatile way for preparing active materials. Size, composition, morphology and organization/architecture of supported metal NPs can be controlled by playing with the type of metal, metal precursor, reaction media composition (stronger or weaker reducing media) and different supports employed. Moreover, direct correlation between physical (size, morphology, organization) and chemical properties (composition, surface chemistry) are demonstrated with the systems catalytic behaviour, yield and selectivity, exemplified with N-alkylation reaction of amines with alcohols.Catalyseurs Nanostructurés en Systèmes Non Conventionnel

ScCO2 assisted preparation of supported metal NPs. Application to catalyst design.

Designing and developing materials with specific properties are nowadays important tasks. These could be achieved by choosing the adequate conditions, from a myriad of possibilities, being aware that slight changes in the preparation method could have major impact on the final material. With the work presented here, we are showing that kinetically controlled surface nano-structuring (NPs formation and deposition over solid supports) in scCO2 is a versatile way for preparing active materials. Size, composition, morphology and organization/architecture of supported metal NPs can be controlled by playing with the type of metal, metal precursor, reaction media composition (stronger or weaker reducing media) and different supports employed. Moreover, direct correlation between physical (size, morphology, organization) and chemical properties (composition, surface chemistry) are demonstrated with the systems catalytic behaviour, yield and selectivity, exemplified with N-alkylation reaction of amines with alcohols.Catalyseurs Nanostructurés en Systèmes Non Conventionnel

Pd@[nBu4][Br] as a simple catalytic system for N-alkylation reactions with alcohols

Palladium nanoparticles, simply and briefly generated in commercial and cheap onium salts using supercritical carbon dioxide, have been found to be an effective catalytic system for additive free N-alkylation reaction using alcohols via cascade oxidation/condensation/reduction steps

Bi(OTf)₃-Catalyzed Cycloisomerization of Aryl-Allenes

Intramolecular hydroarylation of allenes was achieved under very mild conditions using bismuth(III) triflate as the catalyst. Efficient functionalization of activated and nonactivated aromatic nuclei led to C–C bond formation through a formal Ar–H activation. A tandem bis-hydroarylation of the allene moiety was also developed giving access to various interesting polycyclic structures

Simple salts of abundant metals (Fe, Bi, and Ti) supported on montmorillonite as efficient and recyclable catalysts for regioselective intramolecular and intermolecular hydroalkoxylation reactions of double bonds and tandem processes

The transfer of catalytic hydroalkoxylation reactions of olefins from homogeneous to heterogeneous conditions has been studied using two types of solid catalysts, namely montmorillonite (MMT) doped with metal cations and metal nanoparticles supported on oxides. In the case of intramolecular reactions, 38–99% yields of cyclic ethers have been obtained using Fe-MMT and Bi-MMT both in CH3NO2 and dimethyl carbonate (DMC) compared with other supported metal salts or metal nanoparticles. In the case of more challenging intermolecular reactions, conversions up to 72% and yields up to 54% were obtained with metal-doped MMT as well, such as Fe-, Bi-, and Ti-MMT. In this paper, we detail the substrate scope and limitations for both classes of reactions and tandem processes, their transposition in flow and some mechanistic insights concerning the active species, in processes identified as truly heterogeneously catalysed. As a general trend, it was observed that trisubstituted double bonds allowed the best results both in intra- and intermolecular reactions. The transfer of homogeneous catalysts onto heterogeneous ones in the case of Fe-MMT and Bi-MMT was successful and even allowed enhanced catalytic activities in the case of Bi-MMT.Catalyseurs Nanostructurés en Systèmes Non Conventionnel

Bi(OTf)₃-Catalyzed Cycloisomerization of Aryl-Allenes

Intramolecular hydroarylation of allenes was achieved under very mild conditions using bismuth(III) triflate as the catalyst. Efficient functionalization of activated and nonactivated aromatic nuclei led to C–C bond formation through a formal Ar–H activation. A tandem bis-hydroarylation of the allene moiety was also developed giving access to various interesting polycyclic structures

Synthesis of Borinic Acids and Borinate Adducts Using Diisopropylaminoborane

<i>In situ</i> formation of aryl Grignard under Barbier condition and diisopropylaminoborane as boron source allows a complete control of the addition onto the boron electrophile. Analytically pure borinic acid derivatives were produced at the gram scale without column chromatography and isolated as borinates adducts, with ethanolamine or 8-hydroxyquinoline, after workup