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Carlos Roque D. Correia - One of the best experts on this subject based on the ideXlab platform.
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The palladium-catalyzed Heck Arylation of olefins with arenediazonium salts as a sustainable strategy in organic synthesis
Current Opinion in Green and Sustainable Chemistry, 2020Co-Authors: Caio C. Oliveira, Carlos Roque D. CorreiaAbstract:The palladium-catalyzed Heck Arylation of olefins using arenediazonium salts, known as the Heck–Matsuda reaction, constitutes an effective, green, and sustainable way to synthesize functionalized aryl intermediates for organic synthesis. The present review highlights this strategy focusing on some selected examples from our laboratory. The examples include the substrate-directed Arylation of olefins — covalent and noncovalent strategies — and their application in the total syntheses of many pharmacologically active compounds, commercial drugs, and/or functional compounds.
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Quaternary Stereogenic Centers through Enantioselective Heck Arylation of Acyclic Olefins with Aryldiazonium Salts: Application in a Concise Synthesis of (R)-Verapamil.
Angewandte Chemie (International ed. in English), 2015Co-Authors: Caio C. Oliveira, Andreas Pfaltz, Carlos Roque D. CorreiaAbstract:We describe herein a highly regio- and enantioselective Pd-catalyzed Heck Arylation of unactivated trisubstituted acyclic olefins to provide all-carbon quaternary stereogenic centers. Chiral N,N ligands of the pyrimidine- and pyrazino-oxazoline class were developed for that purpose, providing the desired products in good to high yields with enantiomeric ratios up to >99:1. Both linear and branched substituents on the olefins were well-tolerated. The potential of this new method is demonstrated by the straightforward synthesis of several O-methyl lactols and lactones containing quaternary stereocenters, together with a concise enantioselective total synthesis of the calcium channel blocker verapamil.
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Chemo‐, Regio‐ and Stereoselective Heck Arylation of Allylated Malonates: Mechanistic Insights by ESI‐MS and Synthetic Application Toward 5‐Arylmethyl‐γ‐lactones.
ChemInform, 2015Co-Authors: Caio C. Oliveira, Marcelo V. Marques, Marla Narciso Godoi, Thaís Regiani, Vanessa G. Santos, Emerson A. F. Dos Santos, Marcos N. Eberlin, Carlos Roque D. CorreiaAbstract:The Heck Arylation of allylated malonate (I) employing aryldiazonium salts (II) as the aryl-transfer agents is described.
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chemo regio and stereoselective Heck Arylation of allylated malonates mechanistic insights by esi ms and synthetic application toward 5 arylmethyl γ lactones
ChemInform, 2015Co-Authors: Caio C. Oliveira, Marcelo V. Marques, Marla Narciso Godoi, Thaís Regiani, Vanessa G. Santos, Marcos N. Eberlin, Emerson Dos A F Santos, Carlos Roque D. CorreiaAbstract:The Heck Arylation of allylated malonate (I) employing aryldiazonium salts (II) as the aryl-transfer agents is described.
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Chemo-, regio- and stereoselective Heck Arylation of allylated malonates: mechanistic insights by ESI-MS and synthetic application toward 5-arylmethyl-γ-lactones.
Organic letters, 2014Co-Authors: Caio C. Oliveira, Marcelo V. Marques, Marla Narciso Godoi, Thaís Regiani, Vanessa G. Santos, Emerson A. F. Dos Santos, Marcos N. Eberlin, Carlos Roque D. CorreiaAbstract:We describe herein a general method for the controlled Heck Arylation of allylated malonates. Both electron-rich and electron-poor aryldiazonium salts were readily employed as the aryl-transfer agents in good yields and in high chemo-, regio-, and stereoselectivity without formation of decarboxylated byproducts. Reaction monitoring via ESI-MS was used to support the formation of chelated Pd species through the catalytic cycle. Additionally, some Heck adducts were successfully used in the total synthesis of pharmacologically active γ-lactones.
Jianliang Xiao - One of the best experts on this subject based on the ideXlab platform.
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palladium catalyzed regioselective and stereoselective oxidative Heck Arylation of allylamines with arylboronic acids
ChemInform, 2013Co-Authors: Lingjuan Zhang, Chaonan Dong, Chenjun Ding, Jing Chen, Weijun Tang, Jianliang XiaoAbstract:A general and convenient method for the oxidative Heck Arylation of both N-mono- and N,N-diprotected allylic amines under mild conditions is developed.
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Palladium‐Catalyzed Regioselective and Stereoselective Oxidative Heck Arylation of Allylamines with Arylboronic Acids.
ChemInform, 2013Co-Authors: Lingjuan Zhang, Chaonan Dong, Chenjun Ding, Jing Chen, Weijun Tang, Jianliang XiaoAbstract:A general and convenient method for the oxidative Heck Arylation of both N-mono- and N,N-diprotected allylic amines under mild conditions is developed.
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Palladium-Catalyzed Regioselective and Stereoselective Oxidative Heck Arylation of Allylamines with Arylboronic Acids
Advanced Synthesis & Catalysis, 2013Co-Authors: Lingjuan Zhang, Chaonan Dong, Chenjun Ding, Jing Chen, Weijun Tang, Jianliang XiaoAbstract:A general and convenient palladium-catalyzed oxidative Heck Arylation of both N-protected and N,N-diprotected allylic amines with arylboronic acids under mild conditions has been developed. The catalyst system, consisting of Pd(OAc)2 (palladium acetate), AgOAc (silver acetate) and KHF2 (potassium hydrogen fluoride), could efficiently catalyze the coupling reaction in acetone without the aid of any ligand, leading exclusively to the γ-arylated allylic amine products in good to excellent yields. This method is highlighted with excellent regio- and stereocontrol and remarkable functional group tolerance. The carbamate moiety in allylic amine substrates is of crucial importance to the catalytic performance, and the chelation between the carbonyl O (oxygen) and Pd (palladium) atoms is believed to be responsible for the high regioselectivity and stereoselectivity observed.
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Feeding the Heck Reaction with Alcohol: One-Pot Synthesis of Stilbenes from Aryl Alcohols and Bromides.
ChemInform, 2012Co-Authors: Paul Colbon, Jonathan H. Barnard, Purdie Mark, Keith R. Mulholland, Ivan V. Kozhevnikov, Jianliang XiaoAbstract:The reaction proceeds via selective dehydration of alcohols to styrenes followed by a Pd-catalyzed Heck Arylation to afford a variety of functionalized stilbenes in one-pot manner.
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synthesis of oxygen heterocycles by regioselective Heck reaction
ChemInform, 2011Co-Authors: Matthew Mcconville, Jiwu Ruan, John Blacker, Jianliang XiaoAbstract:Regioselective Heck Arylation of unsaturated alcohols followed by cyclization affords 2,2-disubstituted tetrahydrofurans and tetrahydropyrans in a convenient one-pot fashion.
Laurent Djakovitch - One of the best experts on this subject based on the ideXlab platform.
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Base directed palladium catalysed Heck Arylation of acrolein diethyl acetal in water
Applied Catalysis A: General, 2014Co-Authors: Walid Al-maksoud, Catherine Pinel, Stephane Menuel, Eric Monflier, Mohamad Jahjah, Laurent DjakovitchAbstract:a b s t r a c t The selective Heck Arylation of acrolein diethyl acetal catalysed by (Pd(NH3)4)Cl2 in the presence of RAME--CD in water as solvent is described. Depending on the base (i.e. NaOAc or HN(i-Pr)2) good to high selectivity's towards, respectively, the cinnamaldehydes 2 or the 3-arylpropionic esters 1 were achieved. The results support that depending on the base different palladium intermediate complexes are formed. Using NaOAc, {(ArPdX(H2O)2)} complex is preferentially generated giving the cinnamaldehyde 2. On the other hand, in the presence of HN(i-Pr)2, a L-type ligand, (ArPdX(HN(i-Pr)2(H2O)) or (ArPdX(HN(i- Pr)2(HN(i-Pr)2)) will be generated leading to the formation of the 3-arylpropionic ester 1. For the last, coordinated amine participates very probably to the formation of the esters through intramolecular syn -H elimination. © 2013 Elsevier B.V. All rights reserved.
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Efficient Heterogeneously Palladium‐Catalysed Heck Arylation of Acrolein Diethyl Acetal. Selective Synthesis of Cinnamaldehydes or 3‐Arylpropionic Esters
Advanced Synthesis & Catalysis, 2007Co-Authors: Sébastien Noël, Catherine Pinel, C. Luo, Laurent DjakovitchAbstract:A heterogeneous tetrakis-ACHTUNGTRENUNG(ammine)palladium-NaYzeolite {[PdACHTUNGTRENUNG(NH3)4]/NaY} catalyst was applied successfully to the Heck Arylation of acrolein diethyl acetal using a large variety of aryl and heteroaryl bromides. Depending on the reaction conditions (Heck versus Cacchi) good to high selectivities toward the 3-arylpropionic esters or to the cinnamaldehydes were achieved, respectively. Under classical Heck conditions, while the catalyst was found to be stable over the two first runs, it showed significant loss of activity from the third cycle. Under Cacchi conditions, the catalyst could not be reused as it led to high dehalogenation rates. All results indicate that the reactions proceed through dissolved palladium species in the bulk solution (leaching). As observed by transmission electronic microscopic (TEM) analyses, while these species can be trapped and stabilised by the zeolite framework under the Heck conditions, they tend to form large palladium(0) aggregates under the Cacchi conditions leading to dehalogenation rather than to the expected Heck coupling.
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Influence of the catalytic conditions on the selectivity of the Pd-catalyzed Heck Arylation of acrolein derivatives
Tetrahedron Letters, 2006Co-Authors: Sébastien Noël, Laurent Djakovitch, Catherine PinelAbstract:Abstract The Heck Arylation of acrolein with a variety of condensed aryl and heteroaryl halides is described. Depending on the substrate, up to 87% isolated yield to the expected aldehydes was achieved. When the reaction was run on diethylacetal acrolein, the choice of catalytic system dramatically affected the selectivity of the reaction: the catalyst system based on Herrmann’s palladacycle complex gave mainly saturated esters 2 , whereas Cacchi’s conditions led to the formation of α,β-unsaturated aldehydes 1 .
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Heck Arylation of α,β‐Unsaturated Aldehydes
Advanced Synthesis & Catalysis, 2003Co-Authors: A. Nejjar, Catherine Pinel, Laurent DjakovitchAbstract:The Heck Arylation of α,β-unsaturated aldehydes is strongly dependent on the catalyst, the solvent and the base. Optimized conditions yielded either selectively cinnamyl derivatives (83%) or double Arylation products (88% based on aryl conversion). A new α-Arylation of β,β-disubstituted acrolein is also realized.
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Heck Arylation of α,β-Unsaturated Aldehydes
Advanced Synthesis & Catalysis, 2003Co-Authors: A. Nejjar, Catherine Pinel, Laurent DjakovitchAbstract:The Heck Arylation of α,β-unsaturated aldehydes is strongly dependent on the catalyst, the solvent and the base. Optimized conditions yielded either selectively cinnamyl derivatives (83%) or double Arylation products (88% based on aryl conversion). A new α-Arylation of β,β-disubstituted acrolein is also realized.
Adriano L. Monteiro - One of the best experts on this subject based on the ideXlab platform.
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the synthesis of non symmetrical stilbene analogs of trans resveratrol using the same pd catalyst in a sequential double Heck Arylation of ethylene
Applied Organometallic Chemistry, 2011Co-Authors: Sabrina M. Nobre, Mauro N. Muniz, Marcus Seferin, Wagner Menezes Da Silva, Adriano L. MonteiroAbstract:We have developed a sequential and selective Pd-catalyzed double-Heck Arylation of ethylene that results in non-symmetrical nitro-stilbene analogs of trans-resveratrol at excellent yields. A catalytic system consisting of Pd(OAc)2 and P(o-tolyl)3 permitted us to carry out the two consecutive Heck Arylations without losing activity from the first to the second Heck reaction. After the first Heck Arylation of ethylene, no isolation or additional catalyst loading is required for the second Heck Arylation reaction. This protocol was applied to the synthesis of methylated trans-resveratrol, which was obtained at a 65% overall yield. Copyright © 2011 John Wiley & Sons, Ltd.
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The synthesis of non‐symmetrical stilbene analogs of trans‐resveratrol using the same Pd catalyst in a sequential double‐Heck Arylation of ethylene
Applied Organometallic Chemistry, 2011Co-Authors: Sabrina M. Nobre, Mauro N. Muniz, Marcus Seferin, Wagner Menezes Da Silva, Adriano L. MonteiroAbstract:We have developed a sequential and selective Pd-catalyzed double-Heck Arylation of ethylene that results in non-symmetrical nitro-stilbene analogs of trans-resveratrol at excellent yields. A catalytic system consisting of Pd(OAc)2 and P(o-tolyl)3 permitted us to carry out the two consecutive Heck Arylations without losing activity from the first to the second Heck reaction. After the first Heck Arylation of ethylene, no isolation or additional catalyst loading is required for the second Heck Arylation reaction. This protocol was applied to the synthesis of methylated trans-resveratrol, which was obtained at a 65% overall yield. Copyright © 2011 John Wiley & Sons, Ltd.
Catherine Pinel - One of the best experts on this subject based on the ideXlab platform.
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Base directed palladium catalysed Heck Arylation of acrolein diethyl acetal in water
Applied Catalysis A: General, 2014Co-Authors: Walid Al-maksoud, Catherine Pinel, Stephane Menuel, Eric Monflier, Mohamad Jahjah, Laurent DjakovitchAbstract:a b s t r a c t The selective Heck Arylation of acrolein diethyl acetal catalysed by (Pd(NH3)4)Cl2 in the presence of RAME--CD in water as solvent is described. Depending on the base (i.e. NaOAc or HN(i-Pr)2) good to high selectivity's towards, respectively, the cinnamaldehydes 2 or the 3-arylpropionic esters 1 were achieved. The results support that depending on the base different palladium intermediate complexes are formed. Using NaOAc, {(ArPdX(H2O)2)} complex is preferentially generated giving the cinnamaldehyde 2. On the other hand, in the presence of HN(i-Pr)2, a L-type ligand, (ArPdX(HN(i-Pr)2(H2O)) or (ArPdX(HN(i- Pr)2(HN(i-Pr)2)) will be generated leading to the formation of the 3-arylpropionic ester 1. For the last, coordinated amine participates very probably to the formation of the esters through intramolecular syn -H elimination. © 2013 Elsevier B.V. All rights reserved.
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Efficient Heterogeneously Palladium‐Catalysed Heck Arylation of Acrolein Diethyl Acetal. Selective Synthesis of Cinnamaldehydes or 3‐Arylpropionic Esters
Advanced Synthesis & Catalysis, 2007Co-Authors: Sébastien Noël, Catherine Pinel, C. Luo, Laurent DjakovitchAbstract:A heterogeneous tetrakis-ACHTUNGTRENUNG(ammine)palladium-NaYzeolite {[PdACHTUNGTRENUNG(NH3)4]/NaY} catalyst was applied successfully to the Heck Arylation of acrolein diethyl acetal using a large variety of aryl and heteroaryl bromides. Depending on the reaction conditions (Heck versus Cacchi) good to high selectivities toward the 3-arylpropionic esters or to the cinnamaldehydes were achieved, respectively. Under classical Heck conditions, while the catalyst was found to be stable over the two first runs, it showed significant loss of activity from the third cycle. Under Cacchi conditions, the catalyst could not be reused as it led to high dehalogenation rates. All results indicate that the reactions proceed through dissolved palladium species in the bulk solution (leaching). As observed by transmission electronic microscopic (TEM) analyses, while these species can be trapped and stabilised by the zeolite framework under the Heck conditions, they tend to form large palladium(0) aggregates under the Cacchi conditions leading to dehalogenation rather than to the expected Heck coupling.
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Influence of the catalytic conditions on the selectivity of the Pd-catalyzed Heck Arylation of acrolein derivatives
Tetrahedron Letters, 2006Co-Authors: Sébastien Noël, Laurent Djakovitch, Catherine PinelAbstract:Abstract The Heck Arylation of acrolein with a variety of condensed aryl and heteroaryl halides is described. Depending on the substrate, up to 87% isolated yield to the expected aldehydes was achieved. When the reaction was run on diethylacetal acrolein, the choice of catalytic system dramatically affected the selectivity of the reaction: the catalyst system based on Herrmann’s palladacycle complex gave mainly saturated esters 2 , whereas Cacchi’s conditions led to the formation of α,β-unsaturated aldehydes 1 .
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Heck Arylation of α,β‐Unsaturated Aldehydes
Advanced Synthesis & Catalysis, 2003Co-Authors: A. Nejjar, Catherine Pinel, Laurent DjakovitchAbstract:The Heck Arylation of α,β-unsaturated aldehydes is strongly dependent on the catalyst, the solvent and the base. Optimized conditions yielded either selectively cinnamyl derivatives (83%) or double Arylation products (88% based on aryl conversion). A new α-Arylation of β,β-disubstituted acrolein is also realized.
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Heck Arylation of α,β-Unsaturated Aldehydes
Advanced Synthesis & Catalysis, 2003Co-Authors: A. Nejjar, Catherine Pinel, Laurent DjakovitchAbstract:The Heck Arylation of α,β-unsaturated aldehydes is strongly dependent on the catalyst, the solvent and the base. Optimized conditions yielded either selectively cinnamyl derivatives (83%) or double Arylation products (88% based on aryl conversion). A new α-Arylation of β,β-disubstituted acrolein is also realized.