Regis Laurent - Academia.edu (original) (raw)

Papers by Regis Laurent

Research paper thumbnail of Decorating step-by-step and independently the surface and the core of dendrons

Journal of Organometallic Chemistry, Apr 1, 2007

Research paper thumbnail of Synthesis and reactivity of small phosphorus-containing dendritic wedges (dendrons)

Arkivoc, Apr 8, 2002

The synthesis of two small dendrons (dendritic wedges) is reported and the reactivity of the func... more The synthesis of two small dendrons (dendritic wedges) is reported and the reactivity of the functionality located at the core is studied. The first dendron has no reactive functionality on the surface, but possesses a vinyl group activated by a P=N-P=S linkage at the core; this vinyl group reacts slowly but cleanly with 2,3-dimethylbutadiene in Diels-Alder additions. The second dendron has aldehyde groups on the surface and one protected phenol group at the core. The deprotection occurs in very mild conditions, leading to a dendron having one phenol and four aldehyde groups. The reactivity of the phenol is demonstrated by the addition of a diisocyanate, affording a carbamate function and the grafting of an isocyanate group at the core of the dendron.

Research paper thumbnail of Varying Topology of Dendrimers − A New Approach toward the Synthesis of Di-Block Dendrimers

European Journal of Inorganic Chemistry, Jul 1, 2001

ABSTRACT A new way to synthesise di-block dendrimers having two types of end groups located in tw... more ABSTRACT A new way to synthesise di-block dendrimers having two types of end groups located in two different areas of their surface is reported. It consists in growing, step-by-step, a second dendritic wedge from the core of a first dendron. This method is mainly applied to the synthesis of di-block dendrimers having phosphanyl groups on one part of the surface.

Research paper thumbnail of Michael-Type Addition of Amines to the Vinyl Core of Dendrons − Application to the Synthesis of Multidendritic Systems

European Journal of Organic Chemistry, Nov 1, 2000

Research paper thumbnail of Grafting of water-soluble phosphines to dendrimers and their use in catalysis: positive dendritic effects in aqueous media

Dalton Transactions, 2009

Research paper thumbnail of Rapid Synthesis of Phosphorus-Containing Dendrimers with Controlled Molecular Architectures: First Example of Surface-Block, Layer-Block, and Segment-Block Dendrimers Issued from the Same Dendron

Journal of the American Chemical Society, Mar 1, 2000

A third generation dendron possessing one activated vinyl group linked to the core and 16 chlorin... more A third generation dendron possessing one activated vinyl group linked to the core and 16 chlorines linked to the surface has been functionalized with various groups at the core (primary amine, phosphine, or azide), and on the surface (aldehyde, tertiary amine, or nitrile). These functionalized dendrons are used as building blocks for the synthesis of several complex dendritic architectures, obtained through core-core, coresurface, or core-core-surface-core couplings using very simple one-step reactions between these functions, such as Michael additions between vinyl and primary amino groups or Staudinger reactions between phosphines and azides. These reactions finally induce the formation of layer-block dendrons, a surface-block dendrimer, a layer-block dendrimer, a layered surface-block dendrimer, and a segment-block dendrimer, all issued from the same original dendron.

Research paper thumbnail of Bifunctional metallodendrimers based on AB5 derivatives of cyclotriphosphazene as core and P,N ligands as terminal functions

Inorganica Chimica Acta, 2014

ABSTRACT The specific functionalization of hexachlorocyclotriphosphazene with one function differ... more ABSTRACT The specific functionalization of hexachlorocyclotriphosphazene with one function different from the five others was used for the synthesis of bifunctional dendrimers having one protected amine linked to the core and either 5 phosphines or 10 phosphine imines (P,N ligands) as terminal groups. In the latter case, reaction with PdCl2(COD) affords the corresponding complexes of the P,N ligands. All compounds were characterized by multinuclear NMR, and particularly by 31P NMR, which proved to be a very precious tool for the characterization of sophisticated structures such as dendrimers.

Research paper thumbnail of Dual properties of water-soluble Ru-PTA complexes of dendrimers: Catalysis and interaction with DNA

Inorganica Chimica Acta, 2018

Phosphorhydrazone dendrimers ended by PTA (1,3,5-triaza-7-phosphaadamantane) derivatives are used... more Phosphorhydrazone dendrimers ended by PTA (1,3,5-triaza-7-phosphaadamantane) derivatives are used for the complexation of ruthenium. The corresponding complexes, either isolated (synthesized ex situ, i.e. preformed) or generated in situ are used as catalysts for the hydration of phenylacetylene in various conditions (ex situ or in situ, quantities, temperature, duration, co-catalyst or not, recycling). The same preformed complexes are tested for their interaction with supercoiled DNA, to afford relaxed DNA.

Research paper thumbnail of Janus carbosilane/phosphorhydrazone dendrimers synthesized by the ‘click’ Staudinger reaction

Tetrahedron Letters, Dec 1, 2013

The first association of carbosilane dendrons (having a phosphine at the focal point) with phosph... more The first association of carbosilane dendrons (having a phosphine at the focal point) with phosphorhydrazone dendrons (having a thiophosphoryl azide at the focal point) has been successfully carried out by 'Staudinger click' reaction. The corresponding Janus dendrimers possess the characteristics of both components; they are oily as the carbosilane dendrons, and they can be easily functionalized as the phosphorhydrazone dendrons.

Research paper thumbnail of Number of terminal groups versus generation of the dendrimer, which criteria influence the catalytic properties?

Tetrahedron Letters, Jul 1, 2012

ABSTRACT We report the synthesis of a dense dendrimer ended by the PTA ligand (1,3,5-triaza-7-pho... more ABSTRACT We report the synthesis of a dense dendrimer ended by the PTA ligand (1,3,5-triaza-7-phosphaadamantane), and the use of the corresponding Rh and Ru complexes for catalysis. The catalytic properties of these dendrimers are compared with those of two other dendrimers: a dendrimer of the same generation but having half the number of ligands, and a dendrimer of the next generation, but having the same number of ligands. The positive influence of the density of catalytic sites on the surface of these dendrimers for alcohol isomerization in water has been evidenced. (C) 2012 Elsevier Ltd. All rights reserved.

Research paper thumbnail of Phosphorus dendrimers: from synthesis to applications

Comptes Rendus Chimie, Aug 1, 2003

... Author Contact Information , E-mail The Corresponding Author , Valérie Maraval, Régis Laurent... more ... Author Contact Information , E-mail The Corresponding Author , Valérie Maraval, Régis Laurent, Cédric-Olivier Turrin, Pierre Sutra, Julien Leclaire, Laurent Griffe ... Fig. 10. Conversion versus time monitored by 1 H NMR for the Knoevenagel condensation of malonitrile with ...

Research paper thumbnail of Accelerated methods of synthesis of phosphorus-containing dendrimers

Journal of Organometallic Chemistry, May 1, 2005

Research paper thumbnail of Organometallic Derivatives of Phosphorus-containing Dendrimers. Synthesis, Properties and Applications in Catalysis

Current Organic Chemistry, Jul 1, 2002

Research paper thumbnail of ChemInform Abstract: Michael-Type Addition of Amines to the Vinyl Core of Dendrons - Application to the Synthesis of Multidendritic Systems

ChemInform, Jan 23, 2001

ABSTRACT Michael-type additions of functionalized amines to CH2= CH-P=N-P=S linkages located at t... more ABSTRACT Michael-type additions of functionalized amines to CH2= CH-P=N-P=S linkages located at the core of phosphorus-containing dendrons allowed for the grafting of functions suitable to join these dendrons together or to various dendritic molecules. This reactivity led to original multidendritic systems incorporating different types of subunits.

Research paper thumbnail of Multidendritic Systems Incorporating Phosphazene Units

Phosphorus Research Bulletin, 1999

From a third generation dendron possessing an activated vinyl group linked to the core and variou... more From a third generation dendron possessing an activated vinyl group linked to the core and various functions on the surface, it is possible to graft both at the core and on the surface a large number of functionalities. The resulting dendrons are building blocks for a rapid synthesis of new multidendritic systems.

Research paper thumbnail of Synthesis and Characterization of Controlled Dendritic Architectures by Association of Two Phosphorus Dendrons Through a Metallic Center

Phosphorus Sulfur and Silicon and The Related Elements, Jun 6, 2009

ABSTRACT The reactions of RuCl2(PPh3)(3) with either a small amino diphosphine or a first-generat... more ABSTRACT The reactions of RuCl2(PPh3)(3) with either a small amino diphosphine or a first-generation phosphorus-containing dendron possessing an aminodiphosphine as the core induce the formation of complexes in which two amino diphosphines are associated through the metallic center. Determination of the structure of the smallest complex by X-ray diffraction shows that the metal is surrounded by a square-based bi-pyramid defined by the four phosphorus atoms of both diphosphines in a single plane, with the chlorine atoms at both summits. The first generation dendrons behave in the same way as the small compound, and allow us to isolate an original bis dendron, associated through the ruthenium atom.

Research paper thumbnail of Dual properties of water-soluble Ru-PTA complexes of dendrimers: Catalysis and interaction with DNA

Inorganica Chimica Acta, 2017

Phosphorhydrazone dendrimers ended by PTA (1,3,5-triaza-7-phosphaadamantane) derivatives are used... more Phosphorhydrazone dendrimers ended by PTA (1,3,5-triaza-7-phosphaadamantane) derivatives are used for the complexation of ruthenium. The corresponding complexes, either isolated (synthesized ex situ, i.e. preformed) or generated in situ are used as catalysts for the hydration of phenylacetylene in various conditions (ex situ or in situ, quantities, temperature, duration, co-catalyst or not, recycling). The same preformed complexes are tested for their interaction with supercoiled DNA, to afford relaxed DNA.

Research paper thumbnail of 1-NewJournalChemistry 2004 Muzart SI

Research paper thumbnail of Janus carbosilane/phosphorhydrazone dendrimers synthesized by the 'click' Staudinger reaction

Tetrahedron Letters, 2013

The first association of carbosilane dendrons (having a phosphine at the focal point) with phosph... more The first association of carbosilane dendrons (having a phosphine at the focal point) with phosphorhydrazone dendrons (having a thiophosphoryl azide at the focal point) has been successfully carried out by 'Staudinger click' reaction. The corresponding Janus dendrimers possess the characteristics of both components; they are oily as the carbosilane dendrons, and they can be easily functionalized as the phosphorhydrazone dendrons.

Research paper thumbnail of Number of terminal groups versus generation of the dendrimer, which criteria influence the catalytic properties?

Tetrahedron Letters, 2012

ABSTRACT We report the synthesis of a dense dendrimer ended by the PTA ligand (1,3,5-triaza-7-pho... more ABSTRACT We report the synthesis of a dense dendrimer ended by the PTA ligand (1,3,5-triaza-7-phosphaadamantane), and the use of the corresponding Rh and Ru complexes for catalysis. The catalytic properties of these dendrimers are compared with those of two other dendrimers: a dendrimer of the same generation but having half the number of ligands, and a dendrimer of the next generation, but having the same number of ligands. The positive influence of the density of catalytic sites on the surface of these dendrimers for alcohol isomerization in water has been evidenced. (C) 2012 Elsevier Ltd. All rights reserved.

Research paper thumbnail of Decorating step-by-step and independently the surface and the core of dendrons

Journal of Organometallic Chemistry, Apr 1, 2007

Research paper thumbnail of Synthesis and reactivity of small phosphorus-containing dendritic wedges (dendrons)

Arkivoc, Apr 8, 2002

The synthesis of two small dendrons (dendritic wedges) is reported and the reactivity of the func... more The synthesis of two small dendrons (dendritic wedges) is reported and the reactivity of the functionality located at the core is studied. The first dendron has no reactive functionality on the surface, but possesses a vinyl group activated by a P=N-P=S linkage at the core; this vinyl group reacts slowly but cleanly with 2,3-dimethylbutadiene in Diels-Alder additions. The second dendron has aldehyde groups on the surface and one protected phenol group at the core. The deprotection occurs in very mild conditions, leading to a dendron having one phenol and four aldehyde groups. The reactivity of the phenol is demonstrated by the addition of a diisocyanate, affording a carbamate function and the grafting of an isocyanate group at the core of the dendron.

Research paper thumbnail of Varying Topology of Dendrimers − A New Approach toward the Synthesis of Di-Block Dendrimers

European Journal of Inorganic Chemistry, Jul 1, 2001

ABSTRACT A new way to synthesise di-block dendrimers having two types of end groups located in tw... more ABSTRACT A new way to synthesise di-block dendrimers having two types of end groups located in two different areas of their surface is reported. It consists in growing, step-by-step, a second dendritic wedge from the core of a first dendron. This method is mainly applied to the synthesis of di-block dendrimers having phosphanyl groups on one part of the surface.

Research paper thumbnail of Michael-Type Addition of Amines to the Vinyl Core of Dendrons − Application to the Synthesis of Multidendritic Systems

European Journal of Organic Chemistry, Nov 1, 2000

Research paper thumbnail of Grafting of water-soluble phosphines to dendrimers and their use in catalysis: positive dendritic effects in aqueous media

Dalton Transactions, 2009

Research paper thumbnail of Rapid Synthesis of Phosphorus-Containing Dendrimers with Controlled Molecular Architectures: First Example of Surface-Block, Layer-Block, and Segment-Block Dendrimers Issued from the Same Dendron

Journal of the American Chemical Society, Mar 1, 2000

A third generation dendron possessing one activated vinyl group linked to the core and 16 chlorin... more A third generation dendron possessing one activated vinyl group linked to the core and 16 chlorines linked to the surface has been functionalized with various groups at the core (primary amine, phosphine, or azide), and on the surface (aldehyde, tertiary amine, or nitrile). These functionalized dendrons are used as building blocks for the synthesis of several complex dendritic architectures, obtained through core-core, coresurface, or core-core-surface-core couplings using very simple one-step reactions between these functions, such as Michael additions between vinyl and primary amino groups or Staudinger reactions between phosphines and azides. These reactions finally induce the formation of layer-block dendrons, a surface-block dendrimer, a layer-block dendrimer, a layered surface-block dendrimer, and a segment-block dendrimer, all issued from the same original dendron.

Research paper thumbnail of Bifunctional metallodendrimers based on AB5 derivatives of cyclotriphosphazene as core and P,N ligands as terminal functions

Inorganica Chimica Acta, 2014

ABSTRACT The specific functionalization of hexachlorocyclotriphosphazene with one function differ... more ABSTRACT The specific functionalization of hexachlorocyclotriphosphazene with one function different from the five others was used for the synthesis of bifunctional dendrimers having one protected amine linked to the core and either 5 phosphines or 10 phosphine imines (P,N ligands) as terminal groups. In the latter case, reaction with PdCl2(COD) affords the corresponding complexes of the P,N ligands. All compounds were characterized by multinuclear NMR, and particularly by 31P NMR, which proved to be a very precious tool for the characterization of sophisticated structures such as dendrimers.

Research paper thumbnail of Dual properties of water-soluble Ru-PTA complexes of dendrimers: Catalysis and interaction with DNA

Inorganica Chimica Acta, 2018

Phosphorhydrazone dendrimers ended by PTA (1,3,5-triaza-7-phosphaadamantane) derivatives are used... more Phosphorhydrazone dendrimers ended by PTA (1,3,5-triaza-7-phosphaadamantane) derivatives are used for the complexation of ruthenium. The corresponding complexes, either isolated (synthesized ex situ, i.e. preformed) or generated in situ are used as catalysts for the hydration of phenylacetylene in various conditions (ex situ or in situ, quantities, temperature, duration, co-catalyst or not, recycling). The same preformed complexes are tested for their interaction with supercoiled DNA, to afford relaxed DNA.

Research paper thumbnail of Janus carbosilane/phosphorhydrazone dendrimers synthesized by the ‘click’ Staudinger reaction

Tetrahedron Letters, Dec 1, 2013

The first association of carbosilane dendrons (having a phosphine at the focal point) with phosph... more The first association of carbosilane dendrons (having a phosphine at the focal point) with phosphorhydrazone dendrons (having a thiophosphoryl azide at the focal point) has been successfully carried out by 'Staudinger click' reaction. The corresponding Janus dendrimers possess the characteristics of both components; they are oily as the carbosilane dendrons, and they can be easily functionalized as the phosphorhydrazone dendrons.

Research paper thumbnail of Number of terminal groups versus generation of the dendrimer, which criteria influence the catalytic properties?

Tetrahedron Letters, Jul 1, 2012

ABSTRACT We report the synthesis of a dense dendrimer ended by the PTA ligand (1,3,5-triaza-7-pho... more ABSTRACT We report the synthesis of a dense dendrimer ended by the PTA ligand (1,3,5-triaza-7-phosphaadamantane), and the use of the corresponding Rh and Ru complexes for catalysis. The catalytic properties of these dendrimers are compared with those of two other dendrimers: a dendrimer of the same generation but having half the number of ligands, and a dendrimer of the next generation, but having the same number of ligands. The positive influence of the density of catalytic sites on the surface of these dendrimers for alcohol isomerization in water has been evidenced. (C) 2012 Elsevier Ltd. All rights reserved.

Research paper thumbnail of Phosphorus dendrimers: from synthesis to applications

Comptes Rendus Chimie, Aug 1, 2003

... Author Contact Information , E-mail The Corresponding Author , Valérie Maraval, Régis Laurent... more ... Author Contact Information , E-mail The Corresponding Author , Valérie Maraval, Régis Laurent, Cédric-Olivier Turrin, Pierre Sutra, Julien Leclaire, Laurent Griffe ... Fig. 10. Conversion versus time monitored by 1 H NMR for the Knoevenagel condensation of malonitrile with ...

Research paper thumbnail of Accelerated methods of synthesis of phosphorus-containing dendrimers

Journal of Organometallic Chemistry, May 1, 2005

Research paper thumbnail of Organometallic Derivatives of Phosphorus-containing Dendrimers. Synthesis, Properties and Applications in Catalysis

Current Organic Chemistry, Jul 1, 2002

Research paper thumbnail of ChemInform Abstract: Michael-Type Addition of Amines to the Vinyl Core of Dendrons - Application to the Synthesis of Multidendritic Systems

ChemInform, Jan 23, 2001

ABSTRACT Michael-type additions of functionalized amines to CH2= CH-P=N-P=S linkages located at t... more ABSTRACT Michael-type additions of functionalized amines to CH2= CH-P=N-P=S linkages located at the core of phosphorus-containing dendrons allowed for the grafting of functions suitable to join these dendrons together or to various dendritic molecules. This reactivity led to original multidendritic systems incorporating different types of subunits.

Research paper thumbnail of Multidendritic Systems Incorporating Phosphazene Units

Phosphorus Research Bulletin, 1999

From a third generation dendron possessing an activated vinyl group linked to the core and variou... more From a third generation dendron possessing an activated vinyl group linked to the core and various functions on the surface, it is possible to graft both at the core and on the surface a large number of functionalities. The resulting dendrons are building blocks for a rapid synthesis of new multidendritic systems.

Research paper thumbnail of Synthesis and Characterization of Controlled Dendritic Architectures by Association of Two Phosphorus Dendrons Through a Metallic Center

Phosphorus Sulfur and Silicon and The Related Elements, Jun 6, 2009

ABSTRACT The reactions of RuCl2(PPh3)(3) with either a small amino diphosphine or a first-generat... more ABSTRACT The reactions of RuCl2(PPh3)(3) with either a small amino diphosphine or a first-generation phosphorus-containing dendron possessing an aminodiphosphine as the core induce the formation of complexes in which two amino diphosphines are associated through the metallic center. Determination of the structure of the smallest complex by X-ray diffraction shows that the metal is surrounded by a square-based bi-pyramid defined by the four phosphorus atoms of both diphosphines in a single plane, with the chlorine atoms at both summits. The first generation dendrons behave in the same way as the small compound, and allow us to isolate an original bis dendron, associated through the ruthenium atom.

Research paper thumbnail of Dual properties of water-soluble Ru-PTA complexes of dendrimers: Catalysis and interaction with DNA

Inorganica Chimica Acta, 2017

Phosphorhydrazone dendrimers ended by PTA (1,3,5-triaza-7-phosphaadamantane) derivatives are used... more Phosphorhydrazone dendrimers ended by PTA (1,3,5-triaza-7-phosphaadamantane) derivatives are used for the complexation of ruthenium. The corresponding complexes, either isolated (synthesized ex situ, i.e. preformed) or generated in situ are used as catalysts for the hydration of phenylacetylene in various conditions (ex situ or in situ, quantities, temperature, duration, co-catalyst or not, recycling). The same preformed complexes are tested for their interaction with supercoiled DNA, to afford relaxed DNA.

Research paper thumbnail of 1-NewJournalChemistry 2004 Muzart SI

Research paper thumbnail of Janus carbosilane/phosphorhydrazone dendrimers synthesized by the 'click' Staudinger reaction

Tetrahedron Letters, 2013

The first association of carbosilane dendrons (having a phosphine at the focal point) with phosph... more The first association of carbosilane dendrons (having a phosphine at the focal point) with phosphorhydrazone dendrons (having a thiophosphoryl azide at the focal point) has been successfully carried out by 'Staudinger click' reaction. The corresponding Janus dendrimers possess the characteristics of both components; they are oily as the carbosilane dendrons, and they can be easily functionalized as the phosphorhydrazone dendrons.

Research paper thumbnail of Number of terminal groups versus generation of the dendrimer, which criteria influence the catalytic properties?

Tetrahedron Letters, 2012

ABSTRACT We report the synthesis of a dense dendrimer ended by the PTA ligand (1,3,5-triaza-7-pho... more ABSTRACT We report the synthesis of a dense dendrimer ended by the PTA ligand (1,3,5-triaza-7-phosphaadamantane), and the use of the corresponding Rh and Ru complexes for catalysis. The catalytic properties of these dendrimers are compared with those of two other dendrimers: a dendrimer of the same generation but having half the number of ligands, and a dendrimer of the next generation, but having the same number of ligands. The positive influence of the density of catalytic sites on the surface of these dendrimers for alcohol isomerization in water has been evidenced. (C) 2012 Elsevier Ltd. All rights reserved.