The Experts below are selected from a list of 108 Experts worldwide ranked by ideXlab platform

Jérôme Lacour - One of the best experts on this subject based on the ideXlab platform.

  • Enantio- and regioselective CpRu-catalyzed
    2015
    Co-Authors: Carroll Rearrangement, Martina Austeri, Frédéric Buron, Samuel Constant, Jérôme Lacour, David Linder, Jessica Müller, Simone Tortoioli
    Abstract:

    Abstract: The addition of unstabilized carbonyl nucleophiles to allyl-metal fragments still represents a challenge for generating stereoselectively tertiary (and quaternary) stereogenic centers. In this context, the decarboxylative Carroll Rearrangement of secondary and tertiary allyl β-ketoesters is particularly interesting since chiral γ,δ-unsaturated ketones are obtained. Herein, we show that CpRu half-sandwich complexes can, in the presence of selected enantiopure diimine ligands, catalyze this transformation and afford complete conversions and decent level of enantiomeric excess. Zwitterionic adducts of a hexacoordinated phos-phorus anion and CpRu moieties were also associated and shown to generate air-, moisture-, and microwave-stable catalysts that can be readily purified and recycled. Carroll rearrange-ments of allylic β-ketoesters performed with these zwitterionic species occur with better regio- and enantioselectivity

  • enantioselective cpru catalyzed Carroll Rearrangement ligand and metal source importance
    European Journal of Organic Chemistry, 2008
    Co-Authors: David Linder, Frédéric Buron, Samuel Constant, Jérôme Lacour
    Abstract:

    The addition of unstabilized carbonyl nucleophiles to unsymmetrical allyl-metal fragments still represents a challenge to generate stereogenic centers enantio- and regioselectively. In this context, the decarboxylative Carroll Rearrangement of allyl -keto esters is particularly interesting, since chiral,-unsaturated ketones are obtained. Herein, we show that CpRu half-sandwich complexes can, with selected enantiopure pyridine-monooxazoline ligands, catalyze this transformation and afford complete conversions along with good levels of regioselectivity and enantioselectivity. Even more challenging (electron-poor) substrates react (up to 86 % ee, branched/linear ratio 97:03). In addition, the use of an air-stable metal precursor, namely [CpRu(6-naphthalene)][PF6], allows the reaction to be carried out reproducibly evenin non-anhydrous THF with a catalyst loading as low as2 mol-%.

  • Enantio‐ and Regioselective CpRu‐Catalyzed Carroll Rearrangement
    ChemInform, 2008
    Co-Authors: Martina Austeri, Frédéric Buron, Samuel Constant, Jérôme Lacour, David Linder, Jessica Müller, Simone Tortoioli
    Abstract:

    The addition of unstabilized carbonyl nucleophiles to allyl-metal fragments still represents a challenge for generating stereoselectively tertiary (and quaternary) stereogenic centers. In this context, the decarboxylative Carroll Rearrangement of secondary and tertiary allyl β-ketoesters is particularly interesting since chiral γ,δ-unsaturated ketones are obtained. Herein, we show that CpRu half-sandwich complexes can, in the presence of selected enantiopure diimine ligands, catalyze this transformation and afford complete conversions and decent level of enantiomeric excess. Zwitterionic adducts of a hexacoordinated phosphorus anion and CpRu moieties were also associated and shown to generate air-, moisture-, and microwave-stable catalysts that can be readily purified and recycled. Carroll Rearrangements of allylic β-ketoesters performed with these zwitterionic species occur with better regio- and enantioselectivity.

  • Enantio- and regioselective CpRu-catalyzed Carroll Rearrangement
    Pure and Applied Chemistry, 2008
    Co-Authors: Martina Austeri, Frédéric Buron, Samuel Constant, Jérôme Lacour, David Linder, Jessica Müller, Simone Tortoioli
    Abstract:

    The addition of unstabilized carbonyl nucleophiles to allyl-metal fragments still represents a challenge for generating stereoselectively tertiary (and quaternary) stereogenic centers. In this context, the decarboxylative Carroll Rearrangement of secondary and tertiary allyl β-ketoesters is particularly interesting since chiral γ,δ-unsaturated ketones are obtained. Herein, we show that CpRu half-sandwich complexes can, in the presence of selected enantiopure diimine ligands, catalyze this transformation and afford complete conversions and decent level of enantiomeric excess. Zwitterionic adducts of a hexacoordinated phosphorus anion and CpRu moieties were also associated and shown to generate air-, moisture-, and microwave-stable catalysts that can be readily purified and recycled. Carroll Rearrangements of allylic β-ketoesters performed with these zwitterionic species occur with better regio- and enantioselectivity.

  • Enantioselective CpRu‐Catalyzed Carroll Rearrangement – Ligand and Metal Source Importance
    European Journal of Organic Chemistry, 2008
    Co-Authors: David Linder, Frédéric Buron, Samuel Constant, Jérôme Lacour
    Abstract:

    The addition of unstabilized carbonyl nucleophiles to unsymmetrical allyl-metal fragments still represents a challenge to generate stereogenic centers enantio- and regioselectively. In this context, the decarboxylative Carroll Rearrangement of allyl -keto esters is particularly interesting, since chiral,-unsaturated ketones are obtained. Herein, we show that CpRu half-sandwich complexes can, with selected enantiopure pyridine-monooxazoline ligands, catalyze this transformation and afford complete conversions along with good levels of regioselectivity and enantioselectivity. Even more challenging (electron-poor) substrates react (up to 86 % ee, branched/linear ratio 97:03). In addition, the use of an air-stable metal precursor, namely [CpRu(6-naphthalene)][PF6], allows the reaction to be carried out reproducibly evenin non-anhydrous THF with a catalyst loading as low as2 mol-%.

Corinne E Augelli - One of the best experts on this subject based on the ideXlab platform.

  • the Carroll Rearrangement 5 dodecen 2 one
    Organic Syntheses, 2003
    Co-Authors: Stephen R Wilson, Corinne E Augelli
    Abstract:

    The Carroll Rearrangement: 5-dodecen-2-one intermediate: (1-Ethenyl)heptanyl 3-ketobutanoate. reactant: 3-Hydroxy-1-nonene (, 7.5 g, 0.053 mol) intermediate: 2-Carboxy-5-dodecen-2-one. product: 5-Dodecen-2-one. Keywords: acylation; addition, to CO; decarboxylation; esterification, unsubstituted monobasic acids; Rearrangements; Rearrangements; ring opening reactions; assay methods, for butyllithium, with diphenylacetic acid; lithium diisopropylamide (LDA), preparation of; tetrahydrofuran

  • Organic Syntheses - The Carroll Rearrangement: 5‐Dodecen‐2‐one
    Organic Syntheses, 2003
    Co-Authors: Stephen R Wilson, Corinne E Augelli
    Abstract:

    The Carroll Rearrangement: 5-dodecen-2-one intermediate: (1-Ethenyl)heptanyl 3-ketobutanoate. reactant: 3-Hydroxy-1-nonene (, 7.5 g, 0.053 mol) intermediate: 2-Carboxy-5-dodecen-2-one. product: 5-Dodecen-2-one. Keywords: acylation; addition, to CO; decarboxylation; esterification, unsubstituted monobasic acids; Rearrangements; Rearrangements; ring opening reactions; assay methods, for butyllithium, with diphenylacetic acid; lithium diisopropylamide (LDA), preparation of; tetrahydrofuran

Maurice Santelli - One of the best experts on this subject based on the ideXlab platform.

Nicole Ouvrard - One of the best experts on this subject based on the ideXlab platform.

Stephen R Wilson - One of the best experts on this subject based on the ideXlab platform.

  • the Carroll Rearrangement 5 dodecen 2 one
    Organic Syntheses, 2003
    Co-Authors: Stephen R Wilson, Corinne E Augelli
    Abstract:

    The Carroll Rearrangement: 5-dodecen-2-one intermediate: (1-Ethenyl)heptanyl 3-ketobutanoate. reactant: 3-Hydroxy-1-nonene (, 7.5 g, 0.053 mol) intermediate: 2-Carboxy-5-dodecen-2-one. product: 5-Dodecen-2-one. Keywords: acylation; addition, to CO; decarboxylation; esterification, unsubstituted monobasic acids; Rearrangements; Rearrangements; ring opening reactions; assay methods, for butyllithium, with diphenylacetic acid; lithium diisopropylamide (LDA), preparation of; tetrahydrofuran

  • Organic Syntheses - The Carroll Rearrangement: 5‐Dodecen‐2‐one
    Organic Syntheses, 2003
    Co-Authors: Stephen R Wilson, Corinne E Augelli
    Abstract:

    The Carroll Rearrangement: 5-dodecen-2-one intermediate: (1-Ethenyl)heptanyl 3-ketobutanoate. reactant: 3-Hydroxy-1-nonene (, 7.5 g, 0.053 mol) intermediate: 2-Carboxy-5-dodecen-2-one. product: 5-Dodecen-2-one. Keywords: acylation; addition, to CO; decarboxylation; esterification, unsubstituted monobasic acids; Rearrangements; Rearrangements; ring opening reactions; assay methods, for butyllithium, with diphenylacetic acid; lithium diisopropylamide (LDA), preparation of; tetrahydrofuran