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Aiwen Lei - One of the best experts on this subject based on the ideXlab platform.
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Electrochemical Oxidative Decarboxylation and 1,2-aryl migration towards the synthesis of 1,2-diaryl ethers
Chemical Science, 2020Co-Authors: Shengchun Wang, Heng Zhang, Aiwen LeiAbstract:Carboxylic acid compounds are important chemicals and are widely present in various natural products. They are not only nucleophiles, but also radical precursors. Classic transition-metal-catalyzed and photochemical Decarboxylation have shown their excellent site selectivity in radical chemistry. However, electrochemical Decarboxylation with a long history hasn't got enough attention in recent years. In this work, the electrochemical Oxidative Decarboxylation and 1,2-aryl migration of 3,3-diarylpropionic acids have been introduced to construct C–O bonds with alcohols. Remarkably, this transformation can proceed smoothly without metal catalysts and external oxidants.
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Synthesis of oxazoles by silver catalysed Oxidative Decarboxylation–cyclization of α-oxocarboxylates and isocyanides
Chemical communications (Cambridge England), 2015Co-Authors: Zhiyuan Yan, Changliang Bian, Xiao-wen Zhang, Mengfan Wang, Xinlong Gao, Heng Zhang, Aiwen LeiAbstract:A silver catalysed synthesis of oxazoles by the Oxidative Decarboxylation–cyclization of α-oxocarboxylates and isocyanides was developed. This method provided a novel strategy to construct oxazole rings compared to traditional methods. Mechanistic investigations such as operando IR, EPR and radical inhibition experiments were carefully done and confirmed the acyl cation and Ag(II) as the intermediates in this transformation, and the involvement of a radical decarboxylative process.
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synthesis of oxazoles by silver catalysed Oxidative Decarboxylation cyclization of α oxocarboxylates and isocyanides
Chemical Communications, 2015Co-Authors: Zhiyuan Yan, Changliang Bian, Xiao-wen Zhang, Mengfan Wang, Xinlong Gao, Heng Zhang, Aiwen LeiAbstract:A silver catalysed synthesis of oxazoles by the Oxidative Decarboxylation–cyclization of α-oxocarboxylates and isocyanides was developed. This method provided a novel strategy to construct oxazole rings compared to traditional methods. Mechanistic investigations such as operando IR, EPR and radical inhibition experiments were carefully done and confirmed the acyl cation and Ag(II) as the intermediates in this transformation, and the involvement of a radical decarboxylative process.
Valiollah Mirkhani - One of the best experts on this subject based on the ideXlab platform.
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polystyrene bound mn t4pyp a highly efficient and reusable catalyst for biomimetic Oxidative Decarboxylation of carboxylic acids with sodium periodate
Bioorganic & Medicinal Chemistry, 2009Co-Authors: Majid Moghadam, Valiollah Mirkhani, Shahram Tangestaninejad, Iraj Mohammadpoorbaltork, Narges Sirjanian, Somayeh ParandAbstract:In this report, highly efficient Oxidative Decarboxylation of carboxylic acids with sodium periodate catalyzed by a supported manganese(III) porphyrin is described. In the presence of manganese(III) tetra(4-pyridyl)porphyrin supported on cross-linked chloromethylated polystyrene, [Mn(T4PyP)-CMP], as catalyst, carboxylic acids were converted to their corresponding carbonyl compounds via Oxidative Decarboxylation with sodium periodate using imidazole as axial ligand. The oxidation of anti-inflammatory drugs such Indomethacin and Ibuprofen was carried out successfully and the decarboxylated products were obtained. This catalyst can be reused several times without loss of its catalytic activity in the oxidation reactions.
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Rapid and efficient Oxidative Decarboxylation of carboxylic acids with sodium periodate catalyzed by manganese (III) Schiff base complexes.
Bioorganic & medicinal chemistry, 2004Co-Authors: Valiollah Mirkhani, Shahram Tangestaninejad, Majid Moghadam, Maryam MoghbelAbstract:Abstract Rapid and efficient Oxidative decarboxylatoin of α-aryl carboxylic acids was observed. In the chemical system containing Mn(III)-salophen complex as catalyst, carboxylic acids are converted efficiently to the corresponding carbonyl derivatives with sodium periodate. The ability of various Schiff base complexes in the Oxidative Decarboxylation of carboxylic acids was also investigated.
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Efficient Oxidative Decarboxylation of carboxylic acids with sodium periodate catalyzed by supported manganese(III) porphyrin
Bioorganic & medicinal chemistry letters, 2003Co-Authors: Valiollah Mirkhani, Shahram Tangestaninejad, Majid Moghadam, Zohreh KarimianAbstract:Abstract Oxidative Decarboxylation of carboxylic acids by a supported manganese (III) porphyrin was investigated. In the chemical system using 5,10,15,20-tetrakis(4-aminophenyl)porphyrinatomanganese (III) chloride supported on crosslinked chloromethylated polystyrene, [Mn(H 2 NTPP)-CMP], as catalyst, carboxylic acids are converted to the corresponding carbonyl compounds via Oxidative Decarboxylation with sodium periodate.
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Efficient and Mild Oxidative Decarboxylation of Aryl-substituted Carboxylic Acids by Iron and Manganese Porphyrin Periodate Systems
Journal of Chemical Research, 1998Co-Authors: Shahram Tangestaninejad, Valiollah MirkhaniAbstract:The Oxidative Decarboxylation of α-aryl carboxylic acids to the corresponding carbonyl derivatives was observed in catalytic systems containing tetrabutylammonium periodate and metallotetraphenylporphyrins (metal=FeIII or MnIII) at room temperature.
Majid Moghadam - One of the best experts on this subject based on the ideXlab platform.
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polystyrene bound mn t4pyp a highly efficient and reusable catalyst for biomimetic Oxidative Decarboxylation of carboxylic acids with sodium periodate
Bioorganic & Medicinal Chemistry, 2009Co-Authors: Majid Moghadam, Valiollah Mirkhani, Shahram Tangestaninejad, Iraj Mohammadpoorbaltork, Narges Sirjanian, Somayeh ParandAbstract:In this report, highly efficient Oxidative Decarboxylation of carboxylic acids with sodium periodate catalyzed by a supported manganese(III) porphyrin is described. In the presence of manganese(III) tetra(4-pyridyl)porphyrin supported on cross-linked chloromethylated polystyrene, [Mn(T4PyP)-CMP], as catalyst, carboxylic acids were converted to their corresponding carbonyl compounds via Oxidative Decarboxylation with sodium periodate using imidazole as axial ligand. The oxidation of anti-inflammatory drugs such Indomethacin and Ibuprofen was carried out successfully and the decarboxylated products were obtained. This catalyst can be reused several times without loss of its catalytic activity in the oxidation reactions.
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Rapid and efficient Oxidative Decarboxylation of carboxylic acids with sodium periodate catalyzed by manganese (III) Schiff base complexes.
Bioorganic & medicinal chemistry, 2004Co-Authors: Valiollah Mirkhani, Shahram Tangestaninejad, Majid Moghadam, Maryam MoghbelAbstract:Abstract Rapid and efficient Oxidative decarboxylatoin of α-aryl carboxylic acids was observed. In the chemical system containing Mn(III)-salophen complex as catalyst, carboxylic acids are converted efficiently to the corresponding carbonyl derivatives with sodium periodate. The ability of various Schiff base complexes in the Oxidative Decarboxylation of carboxylic acids was also investigated.
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Efficient Oxidative Decarboxylation of carboxylic acids with sodium periodate catalyzed by supported manganese(III) porphyrin
Bioorganic & medicinal chemistry letters, 2003Co-Authors: Valiollah Mirkhani, Shahram Tangestaninejad, Majid Moghadam, Zohreh KarimianAbstract:Abstract Oxidative Decarboxylation of carboxylic acids by a supported manganese (III) porphyrin was investigated. In the chemical system using 5,10,15,20-tetrakis(4-aminophenyl)porphyrinatomanganese (III) chloride supported on crosslinked chloromethylated polystyrene, [Mn(H 2 NTPP)-CMP], as catalyst, carboxylic acids are converted to the corresponding carbonyl compounds via Oxidative Decarboxylation with sodium periodate.
V Semensi - One of the best experts on this subject based on the ideXlab platform.
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The mechanism of tyrosinase-catalysed Oxidative Decarboxylation of alpha-(3,4-dihydroxyphenyl)-lactic acid.
The Biochemical journal, 1991Co-Authors: M Sugumaran, H Dali, V SemensiAbstract:Mushroom tyrosinase, which is known to catalyse the conversion of o-diphenols into o-benzoquinones, has been shown to catalyse the Oxidative Decarboxylation of 3,4-dihydroxymandelic acid [Sugumaran (1986) Biochemistry 25, 4489-4492]. To account for this unusual reaction, a quinone methide intermediate has been proposed. Since all attempts to trap this intermediate ended in vain, mechanistic studies were designed to support the formation of this transient product. Replacement of the alpha-proton in 3,4-dihydroxymandelic acid with a methyl group generates alpha-(3,4-dihydroxyphenyl)-lactic acid, the enzymic oxidation of which should produce 3,4-dihydroxyacetophenone as the end product if the Oxidative Decarboxylation proceeds through the quinone methide intermediate. Accordingly, chemically synthesized alpha-(3,4-dihydroxyphenyl)-lactic acid on enzymic oxidation produced 3,4-dihydroxyacetophenone as the major isolatable product. Non-steady-state kinetic analysis of the enzyme reaction attested to the transient formation of the conventional quinone product. Thus the enzymic oxidation of alpha-(3,4-dihydroxyphenyl)-lactic acid seems to generate the conventional quinone, which, owing to its instability, is rapidly decarboxylated to yield the transient quinone methide. The coupled dieneonephenol re-arrangement and ketol-enol tautomerism transforms the quinone methide into 3,4-dihydroxyacetophenone.
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The mechanism of tyrosinase-catalysed Oxidative Decarboxylation of α-(3,4-dihydroxyphenyl)-lactic acid
Biochemical Journal, 1991Co-Authors: Manickam Sugumaran, H Dali, V SemensiAbstract:Mushroom tyrosinase, which is known to catalyse the conversion of o-diphenols into o-benzoquinones, has been shown to catalyse the Oxidative Decarboxylation of 3,4-dihydroxymandelic acid [Sugumaran (1986) Biochemistry 25, 4489-4492]. To account for this unusual reaction, a quinone methide intermediate has been proposed. Since all attempts to trap this intermediate ended in vain, mechanistic studies were designed to support the formation of this transient product. Replacement of the alpha-proton in 3,4-dihydroxymandelic acid with a methyl group generates alpha-(3,4-dihydroxyphenyl)-lactic acid, the enzymic oxidation of which should produce 3,4-dihydroxyacetophenone as the end product if the Oxidative Decarboxylation proceeds through the quinone methide intermediate. Accordingly, chemically synthesized alpha-(3,4-dihydroxyphenyl)-lactic acid on enzymic oxidation produced 3,4-dihydroxyacetophenone as the major isolatable product. Non-steady-state kinetic analysis of the enzyme reaction attested to the transient formation of the conventional quinone product. Thus the enzymic oxidation of alpha-(3,4-dihydroxyphenyl)-lactic acid seems to generate the conventional quinone, which, owing to its instability, is rapidly decarboxylated to yield the transient quinone methide. The coupled dieneonephenol re-arrangement and ketol-enol tautomerism transforms the quinone methide into 3,4-dihydroxyacetophenone.
Shahram Tangestaninejad - One of the best experts on this subject based on the ideXlab platform.
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polystyrene bound mn t4pyp a highly efficient and reusable catalyst for biomimetic Oxidative Decarboxylation of carboxylic acids with sodium periodate
Bioorganic & Medicinal Chemistry, 2009Co-Authors: Majid Moghadam, Valiollah Mirkhani, Shahram Tangestaninejad, Iraj Mohammadpoorbaltork, Narges Sirjanian, Somayeh ParandAbstract:In this report, highly efficient Oxidative Decarboxylation of carboxylic acids with sodium periodate catalyzed by a supported manganese(III) porphyrin is described. In the presence of manganese(III) tetra(4-pyridyl)porphyrin supported on cross-linked chloromethylated polystyrene, [Mn(T4PyP)-CMP], as catalyst, carboxylic acids were converted to their corresponding carbonyl compounds via Oxidative Decarboxylation with sodium periodate using imidazole as axial ligand. The oxidation of anti-inflammatory drugs such Indomethacin and Ibuprofen was carried out successfully and the decarboxylated products were obtained. This catalyst can be reused several times without loss of its catalytic activity in the oxidation reactions.
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Rapid and efficient Oxidative Decarboxylation of carboxylic acids with sodium periodate catalyzed by manganese (III) Schiff base complexes.
Bioorganic & medicinal chemistry, 2004Co-Authors: Valiollah Mirkhani, Shahram Tangestaninejad, Majid Moghadam, Maryam MoghbelAbstract:Abstract Rapid and efficient Oxidative decarboxylatoin of α-aryl carboxylic acids was observed. In the chemical system containing Mn(III)-salophen complex as catalyst, carboxylic acids are converted efficiently to the corresponding carbonyl derivatives with sodium periodate. The ability of various Schiff base complexes in the Oxidative Decarboxylation of carboxylic acids was also investigated.
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Efficient Oxidative Decarboxylation of carboxylic acids with sodium periodate catalyzed by supported manganese(III) porphyrin
Bioorganic & medicinal chemistry letters, 2003Co-Authors: Valiollah Mirkhani, Shahram Tangestaninejad, Majid Moghadam, Zohreh KarimianAbstract:Abstract Oxidative Decarboxylation of carboxylic acids by a supported manganese (III) porphyrin was investigated. In the chemical system using 5,10,15,20-tetrakis(4-aminophenyl)porphyrinatomanganese (III) chloride supported on crosslinked chloromethylated polystyrene, [Mn(H 2 NTPP)-CMP], as catalyst, carboxylic acids are converted to the corresponding carbonyl compounds via Oxidative Decarboxylation with sodium periodate.
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Efficient and Mild Oxidative Decarboxylation of Aryl-substituted Carboxylic Acids by Iron and Manganese Porphyrin Periodate Systems
Journal of Chemical Research, 1998Co-Authors: Shahram Tangestaninejad, Valiollah MirkhaniAbstract:The Oxidative Decarboxylation of α-aryl carboxylic acids to the corresponding carbonyl derivatives was observed in catalytic systems containing tetrabutylammonium periodate and metallotetraphenylporphyrins (metal=FeIII or MnIII) at room temperature.
