The Experts below are selected from a list of 1545 Experts worldwide ranked by ideXlab platform
Pier Giorgio Cozzi - One of the best experts on this subject based on the ideXlab platform.
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Me2Zn mediated, tert-butylhydroperoxide promoted, catalytic enantioselective Reformatsky Reaction with aldehydes
Chemical communications (Cambridge England), 2008Co-Authors: Pier Giorgio Cozzi, Fides Benfatti, Montse Guiteras Capdevila, Alessandro MignognaAbstract:A practical and highly enantioselective catalytic Reformatsky Reaction with aldehydes using a cheap, commercially available aminoalcohol as ligand is described.
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Dimethylzinc‐Mediated, Oxidatively Promoted Reformatsky Reaction of Ethyl Iodoacetate with Aldehydes and Ketones
Advanced Synthesis & Catalysis, 2008Co-Authors: Pier Giorgio Cozzi, Alessandro Mignogna, Paola VicennatiAbstract:A practical and general Reformatsky Reaction, promoted by oxidants and mediated by dimethylzinc, is described. The Reaction is fast and runs at 0 °C with aldehydes and ketones, under mild Reaction conditions. Preliminary results obtained for the enantioselective version show that inexpensive chiral amino alcohols could be used in the challenging formation of enantioenriched quaternary stereogenic centers.
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dimethylzinc mediated oxidatively promoted Reformatsky Reaction of ethyl iodoacetate with aldehydes and ketones
Advanced Synthesis & Catalysis, 2008Co-Authors: Pier Giorgio Cozzi, Alessandro Mignogna, Paola VicennatiAbstract:A practical and general Reformatsky Reaction, promoted by oxidants and mediated by dimethylzinc, is described. The Reaction is fast and runs at 0 °C with aldehydes and ketones, under mild Reaction conditions. Preliminary results obtained for the enantioselective version show that inexpensive chiral amino alcohols could be used in the challenging formation of enantioenriched quaternary stereogenic centers.
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Practical Chloromanganese-Salen-Catalyzed Enantioselective Reformatsky Reaction with Ketones
Synthesis, 2007Co-Authors: Pier Giorgio Cozzi, Alessandro Mignogna, Luca ZoliAbstract:The first catalytic enantioselective Reformatsky Reaction is realized by a controlled transmetalation of an α-iodo ester with di-methylzinc in the presence of a chloromanganese-Salen complex (20 mol%) as catalyst and 4-phenylpyridine N-oxide (25 mol%) as additive. The zinc enolate is formed under mild conditions at room temperature; it undergoes enantioselective addition to ketones. The Reaction shows broad scope and moderate to good stereoselection and it allows the straightforward preparation of quaternary stereogenic centers.
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a catalytic enantioselective imino Reformatsky Reaction
Advanced Synthesis & Catalysis, 2006Co-Authors: Pier Giorgio CozziAbstract:The admission of air in the Reaction mixture of imine, ethyl iodoacetate and dimethylzinc, in the presence of 20–30 mol % of inexpensive and commercially available N-methylephedrine as the chiral ligand, promoted the Reformatsky Reaction, without the need for other metals or catalysts. Excellent yields (up to 92 %) and enantioselectivities (83–94 %) were obtained for the tested substrates. The Reaction shows a broad scope, and all the imines are prepared in situ, using Me2Zn as the dehydrating agent.
Paola Vicennati - One of the best experts on this subject based on the ideXlab platform.
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Dimethylzinc‐Mediated, Oxidatively Promoted Reformatsky Reaction of Ethyl Iodoacetate with Aldehydes and Ketones
Advanced Synthesis & Catalysis, 2008Co-Authors: Pier Giorgio Cozzi, Alessandro Mignogna, Paola VicennatiAbstract:A practical and general Reformatsky Reaction, promoted by oxidants and mediated by dimethylzinc, is described. The Reaction is fast and runs at 0 °C with aldehydes and ketones, under mild Reaction conditions. Preliminary results obtained for the enantioselective version show that inexpensive chiral amino alcohols could be used in the challenging formation of enantioenriched quaternary stereogenic centers.
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dimethylzinc mediated oxidatively promoted Reformatsky Reaction of ethyl iodoacetate with aldehydes and ketones
Advanced Synthesis & Catalysis, 2008Co-Authors: Pier Giorgio Cozzi, Alessandro Mignogna, Paola VicennatiAbstract:A practical and general Reformatsky Reaction, promoted by oxidants and mediated by dimethylzinc, is described. The Reaction is fast and runs at 0 °C with aldehydes and ketones, under mild Reaction conditions. Preliminary results obtained for the enantioselective version show that inexpensive chiral amino alcohols could be used in the challenging formation of enantioenriched quaternary stereogenic centers.
Zhan-jiang Zheng - One of the best experts on this subject based on the ideXlab platform.
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ar binmol derived salan cu ii complex catalyzed silyl Reformatsky Reaction of aromatic aldehydes
ChemInform, 2015Co-Authors: Wei Zhou, Longsheng Zheng, Zhan-jiang ZhengAbstract:A practical and efficient procedure for the selective synthesis of β-hydroxy esters (III) via a silyl-Reformatsky Reaction catalyzed by a Cu(II)-salan complex is developed.
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Ar-BINMOL—Derived Salan—Cu(II) Complex—Catalyzed Silyl-Reformatsky Reaction of Aromatic Aldehydes.
ChemInform, 2015Co-Authors: Wei Zhou, Long‐sheng Zheng, Zhan-jiang ZhengAbstract:A practical and efficient procedure for the selective synthesis of β-hydroxy esters (III) via a silyl-Reformatsky Reaction catalyzed by a Cu(II)-salan complex is developed.
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Ar-BINMOL–Derived Salan–Cu(II) Complex–Catalyzed Silyl-Reformatsky Reaction of Aromatic Aldehydes
Synthetic Communications, 2014Co-Authors: Wei Zhou, Long‐sheng Zheng, Zhan-jiang ZhengAbstract:In this work, we have developed a facile protocol with salan–Cu system for the facile and selective synthesis of β-hydroxyesters via silyl-Reformatsky Reaction with α-silylester and aldehydes. The screening and optimization of Reaction conditions led to the determination of a practical and efficient procedure in which the salan–Cu exhibited promising catalytic activity in dimethylsulfoxide, in which the silyl-Reformatsky Reaction of aromatic aldehydes with α-trimethylsilylmethylacetate gave the corresponding β-hydroxyester derivatives in excellent yields (up to 98%) under fluoride-free Reaction conditions.
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ar binmol derived salan cu ii complex catalyzed silyl Reformatsky Reaction of aromatic aldehydes
Synthetic Communications, 2014Co-Authors: Wei Zhou, Longsheng Zheng, Zhan-jiang ZhengAbstract:In this work, we have developed a facile protocol with salan–Cu system for the facile and selective synthesis of β-hydroxyesters via silyl-Reformatsky Reaction with α-silylester and aldehydes. The screening and optimization of Reaction conditions led to the determination of a practical and efficient procedure in which the salan–Cu exhibited promising catalytic activity in dimethylsulfoxide, in which the silyl-Reformatsky Reaction of aromatic aldehydes with α-trimethylsilylmethylacetate gave the corresponding β-hydroxyester derivatives in excellent yields (up to 98%) under fluoride-free Reaction conditions.
Trevor V Stanbury - One of the best experts on this subject based on the ideXlab platform.
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A versatile synthesis of tricyclic analogues of quinolone antibacterial agents: Use of a novel Reformatsky Reaction
Tetrahedron Letters, 1996Co-Authors: Joseph P. Michael, Charles B. De Koning, Trevor V StanburyAbstract:A simple synthesis of tricyclic analogues of the quinolone antibiotics bearing a diverse range of substituents on the aromatic ring is described. The key steps involve unprecedented Reformatsky Reaction between diethyl bromomalonate and N-arylpyrrolidine-2-thiones 8, followed by cyclisation of the resulting enaminone intermediates 9 in polyphosphoric acid.
Hideya Mizufune - One of the best experts on this subject based on the ideXlab platform.
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a rapid and diverse construction of 6 substituted 5 6 dihydro 4 hydroxy 2 pyrones through double Reformatsky Reaction
Tetrahedron, 2013Co-Authors: Masahiro Mineno, Yasuhiro Sawai, Kazuaki Kanno, Naotaka Sawada, Hideya MizufuneAbstract:Abstract A rapid and diverse synthesis of biologically important 6-substituted-5,6-dihydro-4-hydroxy-2-pyrones through a double Reformatsky Reaction of aldehydes to δ-hydroxy-β-ketoesters followed by lactonization is described. Due to the high functional group tolerance and Reaction site discrimination between aldehyde, nitrile, and ester groups in the substrate, the protocol can provide the dihydropyrones with bromo, nitro, carboxylic acid, and β-ketoester groups, which are suitable for the further derivatizations. Furthermore, the protocol has been successfully applied to the rapid total synthesis of naturally occurring Yangonin.
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Double Reformatsky Reaction: divergent synthesis of δ-hydroxy-β-ketoesters.
The Journal of organic chemistry, 2013Co-Authors: Masahiro Mineno, Yasuhiro Sawai, Kazuaki Kanno, Naotaka Sawada, Hideya MizufuneAbstract:The double Reformatsky Reaction, tandem addition of two molecules of zinc alkanoate to a carbonyl compound, and its synthetic application to a series of δ-hydroxy-β-ketoesters has been developed. The key to accelerate the double Reformatsky Reaction is considered to be a complex-induced proximity effect of the in situ generated zinc alkoxide coordinated with the pyridyl group of the substrate or bidentate amines. A noteworthy feature of the Reaction system is its high tolerance of functional groups due to the moderate nucleophilicity of organozinc reagents and the mild Reaction conditions. Moreover, spectroscopic and crystallographic analyses of the zinc complex of the double Reformatsky product support the proposed mechanism of Reaction site discrimination for ketones, aldehydes, nitriles, carboxylic acid anhydrides, and esters.
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Double Reformatsky Reaction: Divergent Synthesis of δ‑Hydroxy-β-ketoesters
2013Co-Authors: Masahiro Mineno, Yasuhiro Sawai, Kazuaki Kanno, Naotaka Sawada, Hideya MizufuneAbstract:The double Reformatsky Reaction, tandem addition of two molecules of zinc alkanoate to a carbonyl compound, and its synthetic application to a series of δ-hydroxy-β-ketoesters has been developed. The key to accelerate the double Reformatsky Reaction is considered to be a complex-induced proximity effect of the in situ generated zinc alkoxide coordinated with the pyridyl group of the substrate or bidentate amines. A noteworthy feature of the Reaction system is its high tolerance of functional groups due to the moderate nucleophilicity of organozinc reagents and the mild Reaction conditions. Moreover, spectroscopic and crystallographic analyses of the zinc complex of the double Reformatsky product support the proposed mechanism of Reaction site discrimination for ketones, aldehydes, nitriles, carboxylic acid anhydrides, and esters