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Takayoshi Arai - One of the best experts on this subject based on the ideXlab platform.
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chiral bis Imidazolidine pyridine cu complex catalyzed enantioselective 3 2 cycloaddition of azomethine imines with propiolates
Molecules, 2012Co-Authors: Takayoshi Arai, Yuta OginoAbstract:[3+2] Cycloaddition of azomethine imines with electron-deficient terminal alkynes was smoothly catalyzed by a chiral bis(Imidazolidine)pyridine-CuOAc complex to give bicyclic pyrazolo[1,2-a]pyrazolone derivatives with up to 74% ee.
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chiral bis Imidazolidine pyridine cu otf 2 catalytic asymmetric endo selective 3 2 cycloaddition of imino esters with nitroalkenes
ChemInform, 2010Co-Authors: Takayoshi Arai, Asami Mishiro, Naota Yokoyama, Kuniko Suzuki, Hiroyasu SatoAbstract:A new bis(Imidazolidine)pyridine ligand is easily synthesized in a single condensation of 2,6-pyridyl bisaldehyde and optically active diphenylethylenediamine.
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chiral bis Imidazolidine pyridine cu otf 2 catalytic asymmetric endo selective 3 2 cycloaddition of imino esters with nitroalkenes
Journal of the American Chemical Society, 2010Co-Authors: Takayoshi Arai, Asami Mishiro, Naota Yokoyama, Kuniko Suzuki, Hiroyasu SatoAbstract:The novel C2-symmetric bis(Imidazolidine)pyridine (PyBidine) ligand was easily synthesized in a single condensation of 2,6-pyridyl aldehyde and optically active (S,S)-diphenylethylenediamine. In the C2-symmetric PyBidine−Cu(OTf)2 complex, Imidazolidine rings act as “chiral fences” to shield the first and third quadrants. Use of the PyBidine−Cu(OTf)2 complex as a catalyst enabled the highly endo-selective reaction of imino esters and nitroalkenes to give the adducts in up to 99% ee.
Hiroyasu Sato - One of the best experts on this subject based on the ideXlab platform.
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chiral bis Imidazolidine pyridine cu otf 2 catalytic asymmetric endo selective 3 2 cycloaddition of imino esters with nitroalkenes
ChemInform, 2010Co-Authors: Takayoshi Arai, Asami Mishiro, Naota Yokoyama, Kuniko Suzuki, Hiroyasu SatoAbstract:A new bis(Imidazolidine)pyridine ligand is easily synthesized in a single condensation of 2,6-pyridyl bisaldehyde and optically active diphenylethylenediamine.
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chiral bis Imidazolidine pyridine cu otf 2 catalytic asymmetric endo selective 3 2 cycloaddition of imino esters with nitroalkenes
Journal of the American Chemical Society, 2010Co-Authors: Takayoshi Arai, Asami Mishiro, Naota Yokoyama, Kuniko Suzuki, Hiroyasu SatoAbstract:The novel C2-symmetric bis(Imidazolidine)pyridine (PyBidine) ligand was easily synthesized in a single condensation of 2,6-pyridyl aldehyde and optically active (S,S)-diphenylethylenediamine. In the C2-symmetric PyBidine−Cu(OTf)2 complex, Imidazolidine rings act as “chiral fences” to shield the first and third quadrants. Use of the PyBidine−Cu(OTf)2 complex as a catalyst enabled the highly endo-selective reaction of imino esters and nitroalkenes to give the adducts in up to 99% ee.
Augusto Rivera - One of the best experts on this subject based on the ideXlab platform.
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crystal structure of the di mannich base 4 4 di chloro 3 3 5 5 tetra methyl 2 2 Imidazolidine 1 3 diylbis methyl ene diphenol
Acta Crystallographica Section E: Crystallographic Communications, 2015Co-Authors: Augusto Rivera, Luz Stella Nerio, Michael BolteAbstract:The title compound, C21H26Cl2N2O2, was prepared in a solvent-free microwave-assisted synthesis, and crystallizes in the orthorhombic space group Pna21. The Imidazolidine ring adopts an envelope conformation and its mean plane is almost perpendicular to the two pendant aromatic rings [dihedral angles = 84.61 (9) and 86.54 (9)°]. The molecular structure shows the presence of two intramolecular O—H⋯N hydrogen bonds between the phenolic hydroxy groups and Imidazolidine N atoms. The two 3-chloro-6-hydroxy-2,4-dimethylbenzyl groups are located in a cis orientation with respect to the Imidazolidine fragment. As a result, the lone pairs of electrons on the N atoms are presumed to be disposed in a syn conformation. This is therefore the first example of an exception to the `rabbit-ears' effect in such 2,2′-[Imidazolidine-1,3-diylbis(methylene)]diphenol derivatives.
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crystal structure of 1 1 Imidazolidine 1 3 diylbis methyl ene bis naphthalen 2 ol
Acta Crystallographica Section E: Crystallographic Communications, 2015Co-Authors: Augusto Rivera, Jaime Riosmotta, Jicli Jose Rojas, Michael BolteAbstract:The crystal structure of the title compound, C25H24N2O2, at 173 K has monoclinic (C2/c) symmetry. The molecule is located on a crystallographic twofold rotation axis with only half a molecule in the asymmetric unit. The Imidazolidine ring adopts a twist conformation, with a twist about the ring C—C bond. The crystal structure shows the anticlinal disposition of the two (2-hydroxynaphthalen-1-yl)methyl substituents of the Imidazolidine ring. The structure displays two intramolecular O—H⋯N hydrogen bonds, each forming an S(6) ring motif.
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Crystal structure of 1,1′-[Imidazolidine-1,3-diylbis(methylene)]bis(naphthalen-2-ol)
Acta Crystallographica Section E: Crystallographic Communications, 2015Co-Authors: Augusto Rivera, Jaime Ríos-motta, Jicli Jose Rojas, Michael BolteAbstract:The crystal structure of the title compound, C25H24N2O2, at 173 K has monoclinic (C2/c) symmetry. The molecule is located on a crystallographic twofold rotation axis with only half a molecule in the asymmetric unit. The Imidazolidine ring adopts a twist conformation, with a twist about the ring C—C bond. The crystal structure shows the anticlinal disposition of the two (2-hydroxynaphthalen-1-yl)methyl substituents of the Imidazolidine ring. The structure displays two intramolecular O—H⋯N hydrogen bonds, each forming an S(6) ring motif.
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6 6 dimethyl 2 2 Imidazolidine 1 3 diyl bis methyl ene diphenol
Acta Crystallographica Section E-structure Reports Online, 2014Co-Authors: Augusto Rivera, Luz Stella Nerio, Michael BolteAbstract:In the title compound, C19H24N2O2, a di-Mannich base derived from 2-methylphenol and 1,3,6,8-tetraazatricyclo[4.4.1.13,8]dodecane, the Imidazolidine ring adopts a twist conformation, with a twist about the ring N—C bond [C—N—C—C torsion angle = −44.34 (14)°]. The two 2-hydroxy-3-methylbenzyl groups are located in trans positions with respect to the Imidazolidine fragment. The structure displays two intramolecular O—H⋯N hydrogen bonds, which each form an S(6) ring motif. In the crystal, the molecules are linked by weak C—H⋯O interactions with a bifurcated acceptor, forming a three-dimensional network.
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6,6′-Dimethyl-2,2′-[Imidazolidine-1,3-diylbis(methylene)]diphenol
Acta Crystallographica Section E-structure Reports Online, 2014Co-Authors: Augusto Rivera, Luz Stella Nerio, Michael BolteAbstract:In the title compound, C19H24N2O2, a di-Mannich base derived from 2-methylphenol and 1,3,6,8-tetraazatricyclo[4.4.1.13,8]dodecane, the Imidazolidine ring adopts a twist conformation, with a twist about the ring N—C bond [C—N—C—C torsion angle = −44.34 (14)°]. The two 2-hydroxy-3-methylbenzyl groups are located in trans positions with respect to the Imidazolidine fragment. The structure displays two intramolecular O—H⋯N hydrogen bonds, which each form an S(6) ring motif. In the crystal, the molecules are linked by weak C—H⋯O interactions with a bifurcated acceptor, forming a three-dimensional network.
Rosario Herranz - One of the best experts on this subject based on the ideXlab platform.
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chameleonic reactivity of α amino nitrile derived ureas synthesis of highly functionalized imidazolidin 2 one and Imidazolidine 2 4 dione derivatives
ChemInform, 2014Co-Authors: Pilar Ventosaandres, Juan A Gonzalezvera, Teresa M Garcialopez, Rosario HerranzAbstract:Neutral, basic or mild acidic reaction conditions are evaluated for N-cyanoalkyl-substituted ureas of type (I) and (III) resulting in cyclization to Imidazolidine derivatives.
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chameleonic reactivity of α amino nitrile derived ureas synthesis of highly functionalized imidazolidin 2 one and Imidazolidine 2 4 dione derivatives
Tetrahedron, 2014Co-Authors: Pilar Ventosaandres, Juan A Gonzalezvera, Teresa M Garcialopez, Rosario HerranzAbstract:Abstract The potential of α-amino nitrile-derived ureas for the synthesis of imidazolidin-2-one derivatives has been studied in the context of a medicinal chemistry project focused on the search of antagonists of the thrombin receptor PAR1. In this study α-amino nitrile-derived ureas have shown chameleonic reactivity. Thus, under neutral, basic or mild acid media they cyclize to 4-iminoimidazolidin-2-one derivatives, which tautomerize to 4-amino-2,3-dihydro-1 H -imidazol-2-ones. This tautomerism triggers epimerization at the C 5 of the Imidazolidine ring, as well as its oxidation. However, they give stable highly functionalized hydantoin derivatives under strong acid media, by a no-epimerizing two-step hydrolysis.
Michael Bolte - One of the best experts on this subject based on the ideXlab platform.
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crystal structure of the di mannich base 4 4 di chloro 3 3 5 5 tetra methyl 2 2 Imidazolidine 1 3 diylbis methyl ene diphenol
Acta Crystallographica Section E: Crystallographic Communications, 2015Co-Authors: Augusto Rivera, Luz Stella Nerio, Michael BolteAbstract:The title compound, C21H26Cl2N2O2, was prepared in a solvent-free microwave-assisted synthesis, and crystallizes in the orthorhombic space group Pna21. The Imidazolidine ring adopts an envelope conformation and its mean plane is almost perpendicular to the two pendant aromatic rings [dihedral angles = 84.61 (9) and 86.54 (9)°]. The molecular structure shows the presence of two intramolecular O—H⋯N hydrogen bonds between the phenolic hydroxy groups and Imidazolidine N atoms. The two 3-chloro-6-hydroxy-2,4-dimethylbenzyl groups are located in a cis orientation with respect to the Imidazolidine fragment. As a result, the lone pairs of electrons on the N atoms are presumed to be disposed in a syn conformation. This is therefore the first example of an exception to the `rabbit-ears' effect in such 2,2′-[Imidazolidine-1,3-diylbis(methylene)]diphenol derivatives.
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crystal structure of 1 1 Imidazolidine 1 3 diylbis methyl ene bis naphthalen 2 ol
Acta Crystallographica Section E: Crystallographic Communications, 2015Co-Authors: Augusto Rivera, Jaime Riosmotta, Jicli Jose Rojas, Michael BolteAbstract:The crystal structure of the title compound, C25H24N2O2, at 173 K has monoclinic (C2/c) symmetry. The molecule is located on a crystallographic twofold rotation axis with only half a molecule in the asymmetric unit. The Imidazolidine ring adopts a twist conformation, with a twist about the ring C—C bond. The crystal structure shows the anticlinal disposition of the two (2-hydroxynaphthalen-1-yl)methyl substituents of the Imidazolidine ring. The structure displays two intramolecular O—H⋯N hydrogen bonds, each forming an S(6) ring motif.
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Crystal structure of 1,1′-[Imidazolidine-1,3-diylbis(methylene)]bis(naphthalen-2-ol)
Acta Crystallographica Section E: Crystallographic Communications, 2015Co-Authors: Augusto Rivera, Jaime Ríos-motta, Jicli Jose Rojas, Michael BolteAbstract:The crystal structure of the title compound, C25H24N2O2, at 173 K has monoclinic (C2/c) symmetry. The molecule is located on a crystallographic twofold rotation axis with only half a molecule in the asymmetric unit. The Imidazolidine ring adopts a twist conformation, with a twist about the ring C—C bond. The crystal structure shows the anticlinal disposition of the two (2-hydroxynaphthalen-1-yl)methyl substituents of the Imidazolidine ring. The structure displays two intramolecular O—H⋯N hydrogen bonds, each forming an S(6) ring motif.
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6 6 dimethyl 2 2 Imidazolidine 1 3 diyl bis methyl ene diphenol
Acta Crystallographica Section E-structure Reports Online, 2014Co-Authors: Augusto Rivera, Luz Stella Nerio, Michael BolteAbstract:In the title compound, C19H24N2O2, a di-Mannich base derived from 2-methylphenol and 1,3,6,8-tetraazatricyclo[4.4.1.13,8]dodecane, the Imidazolidine ring adopts a twist conformation, with a twist about the ring N—C bond [C—N—C—C torsion angle = −44.34 (14)°]. The two 2-hydroxy-3-methylbenzyl groups are located in trans positions with respect to the Imidazolidine fragment. The structure displays two intramolecular O—H⋯N hydrogen bonds, which each form an S(6) ring motif. In the crystal, the molecules are linked by weak C—H⋯O interactions with a bifurcated acceptor, forming a three-dimensional network.
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6,6′-Dimethyl-2,2′-[Imidazolidine-1,3-diylbis(methylene)]diphenol
Acta Crystallographica Section E-structure Reports Online, 2014Co-Authors: Augusto Rivera, Luz Stella Nerio, Michael BolteAbstract:In the title compound, C19H24N2O2, a di-Mannich base derived from 2-methylphenol and 1,3,6,8-tetraazatricyclo[4.4.1.13,8]dodecane, the Imidazolidine ring adopts a twist conformation, with a twist about the ring N—C bond [C—N—C—C torsion angle = −44.34 (14)°]. The two 2-hydroxy-3-methylbenzyl groups are located in trans positions with respect to the Imidazolidine fragment. The structure displays two intramolecular O—H⋯N hydrogen bonds, which each form an S(6) ring motif. In the crystal, the molecules are linked by weak C—H⋯O interactions with a bifurcated acceptor, forming a three-dimensional network.