The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform
Sankaraiah Subramani - One of the best experts on this subject based on the ideXlab platform.
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one pack cross linkable waterborne methyl ethyl Ketoxime blocked polyurethane clay nanocomposite dispersions
Macromolecular Research, 2005Co-Authors: Sankaraiah Subramani, Jung Min Lee, Jung Hyun Kim, In Woo CheongAbstract:One-pack cross-linkable nanocomposites of waterborne methyl ethyl Ketoxime (MEKO)-blocked aromatic polyurethane dispersion (BPUD) reinforced with organoclay (quaternary ammonium salt of Cloisite 25A) were synthesized by the acetone process using 4,4′-methylenedi-p-phenyl diisocyanate (MDI), poly(tetramethylene) glycol (PTMG), dimethylol propionic acid (DMPA), and methyl ethyl Ketoxime (MEKO). Particle size, viscosity, and storage stability of these nanocomposites were investigated. TEM and XRD studies confirmed that the silicate layers of organophilic clay were exfoliated and intercalated at a nanometer-scale in the BPUD matrix.
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One-pack cross-linkable waterborne methyl ethyl Ketoxime-blocked polyurethane/clay nanocomposite dispersions
Macromolecular Research, 2005Co-Authors: Sankaraiah Subramani, Jung Min Lee, Jung Hyun Kim, In Woo CheongAbstract:One-pack cross-linkable nanocomposites of waterborne methyl ethyl Ketoxime (MEKO)-blocked aromatic polyurethane dispersion (BPUD) reinforced with organoclay (quaternary ammonium salt of Cloisite 25A) were synthesized by the acetone process using 4,4′-methylenedi- p -phenyl diisocyanate (MDI), poly(tetramethylene) glycol (PTMG), dimethylol propionic acid (DMPA), and methyl ethyl Ketoxime (MEKO). Particle size, viscosity, and storage stability of these nanocomposites were investigated. TEM and XRD studies confirmed that the silicate layers of organophilic clay were exfoliated and intercalated at a nanometer-scale in the BPUD matrix.
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new development of polyurethane dispersion derived from blocked aromatic diisocyanate
Progress in Organic Coatings, 2003Co-Authors: Sankaraiah Subramani, Youngjun ParkAbstract:Abstract Making water dispersible/reducible blocked-isocyanates facilitates incorporation of blocked-isocyanates into an aqueous dispersion of co-reactant. Anionically modified methyl ethyl Ketoxime (MEKO), e-caprolactam (CL) and 3,5-dimethylpyrazole (DMP) blocked aromatic diisocyanates (toluene 2,4-diisocyanate, TDI and 4,4′-diphenylmethane diisocyanate, MDI) dispersible isocyanate adducts were prepared by introducing ionic pendant groups and characterized by FT-IR, gel permeation chromatography (GPC), differential scanning calorimeter (DSC) and thermo-gravimetric analyses (TGA) techniques. It was found that molecular weights of MDI-based polyisocyanates were higher. Thermal studies showed that the de-blocking temperature of the isocyanate adducts decreases in the order: e-caprolactam>methyl ethyl Ketoxime>DMP. Gelation test was conducted by using the isocyanate adducts with hydroxyl functional aqueous polyurethane dispersion. It was also found that the dispersions of blocked adducts are stable and compatible with polyurethane (polyether and polyester based) and acrylic dispersions.
Zhenghui Guan - One of the best experts on this subject based on the ideXlab platform.
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iron catalyzed cyclization of Ketoxime carboxylates and tertiary anilines for the synthesis of pyridines
Organic Letters, 2016Co-Authors: Mina Zhao, Zhihui Ren, Yaoyu Wang, Zhenghui GuanAbstract:A novel and efficient iron-catalyzed cyclization of Ketoxime carboxylates and N,N-dialkylanilines for the modular synthesis of diverse pyridines was developed. The reaction was initiated by Fe-catalyzed N–O bond cleavage of Ketoxime carboxylates in the presence of tertiary anilines. The methylene carbon on N,N-dialkylanilines functioned as a source of one-carbon synthon in the reaction. The reaction used readily available starting materials, tolerated various functional groups, and afforded 2,4-disubstituted and 2,4,6-trisubstituted pyridines in good to high yields under mild conditions.
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Iron-Catalyzed Cyclization of Ketoxime Carboxylates and Tertiary Anilines for the Synthesis of Pyridines
2016Co-Authors: Mina Zhao, Zhihui Ren, Yaoyu Wang, Zhenghui GuanAbstract:A novel and efficient iron-catalyzed cyclization of Ketoxime carboxylates and N,N-dialkylanilines for the modular synthesis of diverse pyridines was developed. The reaction was initiated by Fe-catalyzed N–O bond cleavage of Ketoxime carboxylates in the presence of tertiary anilines. The methylene carbon on N,N-dialkylanilines functioned as a source of one-carbon synthon in the reaction. The reaction used readily available starting materials, tolerated various functional groups, and afforded 2,4-disubstituted and 2,4,6-trisubstituted pyridines in good to high yields under mild conditions
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copper catalyzed 5 endo trig cyclization of Ketoxime carboxylates a facile synthesis of 2 arylpyrroles
ChemInform, 2014Co-Authors: Mina Zhao, Zhihui Ren, Yaoyu Wang, Zhenghui GuanAbstract:A novel and efficient Cu-catalyzed intermolecular 5-endo-trig cyclization of Ketoxime carboxylates for the synthesis of 2-arylpyrroles is developed.
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Ruthenium-Catalyzed Cyclization of Ketoxime Acetates with DMF for Synthesis of Symmetrical Pyridines.
ChemInform, 2014Co-Authors: Mina Zhao, Zhihui Ren, Yaoyu Wang, Rong-rong Hui, Zhenghui GuanAbstract:The synthesis of tetrasubstituted symmetrical pyridines by a novel ruthenium-catalyzed cyclization of Ketoxime carboxylates with DMF is described.
Yingsheng Zhao - One of the best experts on this subject based on the ideXlab platform.
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Rhodium(III)-Catalyzed Oxidative Annulation of Ketoximes with Sulfonamide: A Direct Approach to Indazoles
Organic letters, 2019Co-Authors: Ning Wang, Lingling Liu, Mengye Zhang, Zhibin Huang, Daqing Shi, Yingsheng ZhaoAbstract:A rhodium(III)-catalyzed intermolecular C–H amination of Ketoxime and iodobenzene diacetate-enabled N–N bond formation in the synthesis of indazoles has been developed. A variety of functional groups were well tolerated, providing the corresponding products in moderate to good yields. Moreover, the nitro-substituted Ketoximes are well compatible in this reaction, leading to the corresponding products in moderate to good yields.
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Rhodium(III)-Catalyzed Oxidative Annulation of Ketoximes with Sulfonamide: A Direct Approach to Indazoles
2019Co-Authors: Ning Wang, Lingling Liu, Mengye Zhang, Zhibin Huang, Daqing Shi, Yingsheng ZhaoAbstract:A rhodium(III)-catalyzed intermolecular C–H amination of Ketoxime and iodobenzene diacetate-enabled N–N bond formation in the synthesis of indazoles has been developed. A variety of functional groups were well tolerated, providing the corresponding products in moderate to good yields. Moreover, the nitro-substituted Ketoximes are well compatible in this reaction, leading to the corresponding products in moderate to good yields
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Ruthenium(II)-Catalyzed C-H Difluoromethylation of Ketoximes: Tuning the Regioselectivity from the meta to the para Position.
Angewandte Chemie (International ed. in English), 2018Co-Authors: Chunchen Yuan, Lei Zhu, Runsheng Zeng, Yu Lan, Yingsheng ZhaoAbstract:A highly para-selective CAr -H difluoromethylation of Ketoxime ethers under ruthenium catalysis has been developed. A wide variety of Ketoxime ethers are compatible with the reaction, which leads to the corresponding para-difluoromethylated products in moderate to good yield. A mechanistic study clearly showed that chelation-assisted cycloruthenation is the key factor in the para selectivity of the difluoromethylation of Ketoxime ethers. Density functional theory was used to gain a theoretical understanding of the para selectivity.
Mina Zhao - One of the best experts on this subject based on the ideXlab platform.
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iron catalyzed cyclization of Ketoxime carboxylates and tertiary anilines for the synthesis of pyridines
Organic Letters, 2016Co-Authors: Mina Zhao, Zhihui Ren, Yaoyu Wang, Zhenghui GuanAbstract:A novel and efficient iron-catalyzed cyclization of Ketoxime carboxylates and N,N-dialkylanilines for the modular synthesis of diverse pyridines was developed. The reaction was initiated by Fe-catalyzed N–O bond cleavage of Ketoxime carboxylates in the presence of tertiary anilines. The methylene carbon on N,N-dialkylanilines functioned as a source of one-carbon synthon in the reaction. The reaction used readily available starting materials, tolerated various functional groups, and afforded 2,4-disubstituted and 2,4,6-trisubstituted pyridines in good to high yields under mild conditions.
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Iron-Catalyzed Cyclization of Ketoxime Carboxylates and Tertiary Anilines for the Synthesis of Pyridines
2016Co-Authors: Mina Zhao, Zhihui Ren, Yaoyu Wang, Zhenghui GuanAbstract:A novel and efficient iron-catalyzed cyclization of Ketoxime carboxylates and N,N-dialkylanilines for the modular synthesis of diverse pyridines was developed. The reaction was initiated by Fe-catalyzed N–O bond cleavage of Ketoxime carboxylates in the presence of tertiary anilines. The methylene carbon on N,N-dialkylanilines functioned as a source of one-carbon synthon in the reaction. The reaction used readily available starting materials, tolerated various functional groups, and afforded 2,4-disubstituted and 2,4,6-trisubstituted pyridines in good to high yields under mild conditions
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copper catalyzed 5 endo trig cyclization of Ketoxime carboxylates a facile synthesis of 2 arylpyrroles
ChemInform, 2014Co-Authors: Mina Zhao, Zhihui Ren, Yaoyu Wang, Zhenghui GuanAbstract:A novel and efficient Cu-catalyzed intermolecular 5-endo-trig cyclization of Ketoxime carboxylates for the synthesis of 2-arylpyrroles is developed.
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Ruthenium-Catalyzed Cyclization of Ketoxime Acetates with DMF for Synthesis of Symmetrical Pyridines.
ChemInform, 2014Co-Authors: Mina Zhao, Zhihui Ren, Yaoyu Wang, Rong-rong Hui, Zhenghui GuanAbstract:The synthesis of tetrasubstituted symmetrical pyridines by a novel ruthenium-catalyzed cyclization of Ketoxime carboxylates with DMF is described.
In Su Kim - One of the best experts on this subject based on the ideXlab platform.
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palladium catalyzed decarboxylative acylation of o methyl Ketoximes with α keto acids
Chemical Communications, 2013Co-Authors: Minyoung Kim, Jihye Park, Satyasheel Sharma, Aejin Kim, Eonjeong Park, Jong Hwan Kwak, Young Hoon Jung, In Su KimAbstract:A mild, practical and efficient palladium-catalyzed decarboxylative ortho-acylation of O-methyl Ketoximes with α-keto acids via C–H bond activation is described. In these reactions, a broad range of O-methyl Ketoximes and α-keto acids undergoes the decarboxylative cross-coupling reactions with high selectivities and good tolerance.
