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Yun-zhi Tang - One of the best experts on this subject based on the ideXlab platform.

  • Supramolecular Interactions Induced Chirality Transmission, Second Harmonic Generation Responses, and Photoluminescent Property of a Pair of Enantiomers from in Situ [2 + 3] Cycloaddition Synthesis
    Crystal Growth & Design, 2016
    Co-Authors: Ji-xing Gao, Jian-bo Xiong, Yu-hui Tan, Yi Liu, He-rui Wen, Yun-zhi Tang
    Abstract:

    Spontaneous resolutions from an in situ Reaction especially for a Sharpless Reaction are really rare. Here we display a new pair of enantiomeric compounds Δ- and Λ-[Mn(4-tzba)(bpy)2·H2O](bpy)·3H2O (labeled as Δ-1 and Λ-1 respectively) (4-tzba = 4-tetrazolbenzoic acid; bpy = 2,2′-bipyridine) from a Sharpless Reaction. They crystallized in the P212121 chiral space group and demonstrated strong second harmonic generation (SHG) responses and red photoluminescence property. The chiral metal conformations were captured by the introduction of the distorted bpy and the in situ synthesized 4-tzba ligands. The hydrogen bonds connecting the 4-tzba and central metal play a crucial role in the chirality transmission, as well as the donor–acceptor type SHG nonlinear response.

  • Spontaneous Resolution, Asymmetric Catalysis, and Fluorescence Properties of Δ- and Λ-[Cu(Tzmp)]n Enantiomers from in Situ [2 + 3] Cycloaddition Synthesis
    Inorganic chemistry, 2015
    Co-Authors: Yun-zhi Tang, Ji-xing Gao, Jian-bo Xiong, Yu-hui Tan, He-rui Wen
    Abstract:

    Although a number of acentric or chiral tetrazole complexes were synthesized from Sharpless Reaction, there are no spontaneous resolution Cu(I)-tetrazole compounds from in situ [2 + 3] cycloaddition synthesis that have been reported before. The first enantiomers Δ- and Λ- of metal tetrazole compound [Cu(Tzmp)]n (1) (HTzmp = 3-tetrazolemethylpyridine) were obtained and isolated from in situ [2 + 3] cycloaddition Reactions of a flexible organic nitrile (3-cyanomethylpyridine) with sodium azide in the presence of CuCl2 as the Lewis acid. Δ-1 and Λ-1 feature a homochiral helical coordination polymeric system and {4(4).6(2)} two-dimensional framework. The photoluminescence study suggests 1 exhibits strong green fluorescence in solid state with maximal emission peaks around 535 nm. Remarkably, the Δ- and Λ- of [Cu(Tzmp)]n (1) catalyzes the enantioselective Henry Reaction with high yield (more than 96%) and certain enantioselectivity (up to 69%).

  • synthesis crystal structures and luminescent properties of zinc and manganese complexes from demko Sharpless Reaction
    Inorganica Chimica Acta, 2009
    Co-Authors: Yun-zhi Tang, Yu-hui Tan, Dong-liang Liu, Xian-ping Luo, Xiao-bing Xie, Zhen-xing Liu
    Abstract:

    Abstract The synthesis and crystal structure of two new complexes (Zn and Mn) containing tetrazolyl ligands are described. In situ [2+3] cycloaddition Reactions of fipronil, (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile) with sodium azide in the presence of ZnCl2 or MnCl2 as a Lewis acid (Demko–Sharpless tetrazole synthesis method) under hydrothermal (solvothermal) Reaction conditions gave [Zn(L)2](H2O)2] · H2O, 1 and [Mn(L)2](H2O)2] · H2O, 2, (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole). The central metals in both complexes are six coordinated, which connected by two water molecules, two nitrogen atoms from different tetrazolyl groups and two nitrogen atoms from pyrazolyl rings respectively. Photoluminescence studies reveal that both title complexes exhibit strong blue fluorescent emissions at λmax = 383 nm for 1 and 411 nm for 2 respectively in the solid state at room temperature.

  • Synthesis, crystal structures and luminescent properties of zinc and manganese complexes from Demko–Sharpless Reaction
    Inorganica Chimica Acta, 2009
    Co-Authors: Yun-zhi Tang, Yu-hui Tan, Dong-liang Liu, Xian-ping Luo, Xiao-bing Xie, Zhen-xing Liu
    Abstract:

    Abstract The synthesis and crystal structure of two new complexes (Zn and Mn) containing tetrazolyl ligands are described. In situ [2+3] cycloaddition Reactions of fipronil, (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile) with sodium azide in the presence of ZnCl2 or MnCl2 as a Lewis acid (Demko–Sharpless tetrazole synthesis method) under hydrothermal (solvothermal) Reaction conditions gave [Zn(L)2](H2O)2] · H2O, 1 and [Mn(L)2](H2O)2] · H2O, 2, (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole). The central metals in both complexes are six coordinated, which connected by two water molecules, two nitrogen atoms from different tetrazolyl groups and two nitrogen atoms from pyrazolyl rings respectively. Photoluminescence studies reveal that both title complexes exhibit strong blue fluorescent emissions at λmax = 383 nm for 1 and 411 nm for 2 respectively in the solid state at room temperature.

Víctor S. Martín - One of the best experts on this subject based on the ideXlab platform.

  • asymmetric epoxidation of allylic alcohols the katsuki Sharpless epoxidation Reaction
    Organic Reactions, 2004
    Co-Authors: Tsutomu Katsuki, Víctor S. Martín
    Abstract:

    In 1980, Sharpless and Katsuki discovered a system for the asymmetric epoxidation of primary allylic alcohols that utilizes Ti(OPr-i)4, a dialkyl tartrate as a chiral ligand, and tert-butyl hydroperoxide as the oxidant. Notably, this Reaction exhibits high levels of enantioselectivity (usually > 90% ee). Like other metal-catalyzed epoxidations, this Reaction also proceeds under mild conditions with good chemical yield and with high regio- and chemoselectivity. Various aspects of this Reaction, including its mechanism, early synthetic applications, and further transformations of the epoxy alcohol product, have been reviewed. In this chapter, the full scope and limitations of this Reaction, its synthetic applications, and typical experimental conditions are described. Keywords: epoxidation; allylic alcohols; Katsuki-Sharpless Reaction; titanium tartrate; mechanism; reactivity; stereoselectivity; chemiselectivity; regioselectivity; product stability; scope; limitations; asymmetric epoxidation. catalysts; primary allylic alcohols; secondary allylic alcohols; asymmetric oxidation; sulfides; selenides; amines; epoxy alcohols; transformations; functional units; Payne rearrangement; ring opening; kinetic resolution; chiral substrates; unfunctionalized olefins; synthesis; nonracemic epoxides; experimental conditions; experimental procedures; tabular survey

  • Organic Reactions - Asymmetric Epoxidation of Allylic Alcohols: the Katsuki–Sharpless Epoxidation Reaction
    Organic Reactions, 1996
    Co-Authors: Tsutomu Katsuki, Víctor S. Martín
    Abstract:

    In 1980, Sharpless and Katsuki discovered a system for the asymmetric epoxidation of primary allylic alcohols that utilizes Ti(OPr-i)4, a dialkyl tartrate as a chiral ligand, and tert-butyl hydroperoxide as the oxidant. Notably, this Reaction exhibits high levels of enantioselectivity (usually > 90% ee). Like other metal-catalyzed epoxidations, this Reaction also proceeds under mild conditions with good chemical yield and with high regio- and chemoselectivity. Various aspects of this Reaction, including its mechanism, early synthetic applications, and further transformations of the epoxy alcohol product, have been reviewed. In this chapter, the full scope and limitations of this Reaction, its synthetic applications, and typical experimental conditions are described. Keywords: epoxidation; allylic alcohols; Katsuki-Sharpless Reaction; titanium tartrate; mechanism; reactivity; stereoselectivity; chemiselectivity; regioselectivity; product stability; scope; limitations; asymmetric epoxidation. catalysts; primary allylic alcohols; secondary allylic alcohols; asymmetric oxidation; sulfides; selenides; amines; epoxy alcohols; transformations; functional units; Payne rearrangement; ring opening; kinetic resolution; chiral substrates; unfunctionalized olefins; synthesis; nonracemic epoxides; experimental conditions; experimental procedures; tabular survey

Yu-hui Tan - One of the best experts on this subject based on the ideXlab platform.

  • Supramolecular Interactions Induced Chirality Transmission, Second Harmonic Generation Responses, and Photoluminescent Property of a Pair of Enantiomers from in Situ [2 + 3] Cycloaddition Synthesis
    Crystal Growth & Design, 2016
    Co-Authors: Ji-xing Gao, Jian-bo Xiong, Yu-hui Tan, Yi Liu, He-rui Wen, Yun-zhi Tang
    Abstract:

    Spontaneous resolutions from an in situ Reaction especially for a Sharpless Reaction are really rare. Here we display a new pair of enantiomeric compounds Δ- and Λ-[Mn(4-tzba)(bpy)2·H2O](bpy)·3H2O (labeled as Δ-1 and Λ-1 respectively) (4-tzba = 4-tetrazolbenzoic acid; bpy = 2,2′-bipyridine) from a Sharpless Reaction. They crystallized in the P212121 chiral space group and demonstrated strong second harmonic generation (SHG) responses and red photoluminescence property. The chiral metal conformations were captured by the introduction of the distorted bpy and the in situ synthesized 4-tzba ligands. The hydrogen bonds connecting the 4-tzba and central metal play a crucial role in the chirality transmission, as well as the donor–acceptor type SHG nonlinear response.

  • Spontaneous Resolution, Asymmetric Catalysis, and Fluorescence Properties of Δ- and Λ-[Cu(Tzmp)]n Enantiomers from in Situ [2 + 3] Cycloaddition Synthesis
    Inorganic chemistry, 2015
    Co-Authors: Yun-zhi Tang, Ji-xing Gao, Jian-bo Xiong, Yu-hui Tan, He-rui Wen
    Abstract:

    Although a number of acentric or chiral tetrazole complexes were synthesized from Sharpless Reaction, there are no spontaneous resolution Cu(I)-tetrazole compounds from in situ [2 + 3] cycloaddition synthesis that have been reported before. The first enantiomers Δ- and Λ- of metal tetrazole compound [Cu(Tzmp)]n (1) (HTzmp = 3-tetrazolemethylpyridine) were obtained and isolated from in situ [2 + 3] cycloaddition Reactions of a flexible organic nitrile (3-cyanomethylpyridine) with sodium azide in the presence of CuCl2 as the Lewis acid. Δ-1 and Λ-1 feature a homochiral helical coordination polymeric system and {4(4).6(2)} two-dimensional framework. The photoluminescence study suggests 1 exhibits strong green fluorescence in solid state with maximal emission peaks around 535 nm. Remarkably, the Δ- and Λ- of [Cu(Tzmp)]n (1) catalyzes the enantioselective Henry Reaction with high yield (more than 96%) and certain enantioselectivity (up to 69%).

  • synthesis crystal structures and luminescent properties of zinc and manganese complexes from demko Sharpless Reaction
    Inorganica Chimica Acta, 2009
    Co-Authors: Yun-zhi Tang, Yu-hui Tan, Dong-liang Liu, Xian-ping Luo, Xiao-bing Xie, Zhen-xing Liu
    Abstract:

    Abstract The synthesis and crystal structure of two new complexes (Zn and Mn) containing tetrazolyl ligands are described. In situ [2+3] cycloaddition Reactions of fipronil, (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile) with sodium azide in the presence of ZnCl2 or MnCl2 as a Lewis acid (Demko–Sharpless tetrazole synthesis method) under hydrothermal (solvothermal) Reaction conditions gave [Zn(L)2](H2O)2] · H2O, 1 and [Mn(L)2](H2O)2] · H2O, 2, (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole). The central metals in both complexes are six coordinated, which connected by two water molecules, two nitrogen atoms from different tetrazolyl groups and two nitrogen atoms from pyrazolyl rings respectively. Photoluminescence studies reveal that both title complexes exhibit strong blue fluorescent emissions at λmax = 383 nm for 1 and 411 nm for 2 respectively in the solid state at room temperature.

  • Synthesis, crystal structures and luminescent properties of zinc and manganese complexes from Demko–Sharpless Reaction
    Inorganica Chimica Acta, 2009
    Co-Authors: Yun-zhi Tang, Yu-hui Tan, Dong-liang Liu, Xian-ping Luo, Xiao-bing Xie, Zhen-xing Liu
    Abstract:

    Abstract The synthesis and crystal structure of two new complexes (Zn and Mn) containing tetrazolyl ligands are described. In situ [2+3] cycloaddition Reactions of fipronil, (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile) with sodium azide in the presence of ZnCl2 or MnCl2 as a Lewis acid (Demko–Sharpless tetrazole synthesis method) under hydrothermal (solvothermal) Reaction conditions gave [Zn(L)2](H2O)2] · H2O, 1 and [Mn(L)2](H2O)2] · H2O, 2, (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole). The central metals in both complexes are six coordinated, which connected by two water molecules, two nitrogen atoms from different tetrazolyl groups and two nitrogen atoms from pyrazolyl rings respectively. Photoluminescence studies reveal that both title complexes exhibit strong blue fluorescent emissions at λmax = 383 nm for 1 and 411 nm for 2 respectively in the solid state at room temperature.

Zhen-xing Liu - One of the best experts on this subject based on the ideXlab platform.

  • synthesis crystal structures and luminescent properties of zinc and manganese complexes from demko Sharpless Reaction
    Inorganica Chimica Acta, 2009
    Co-Authors: Yun-zhi Tang, Yu-hui Tan, Dong-liang Liu, Xian-ping Luo, Xiao-bing Xie, Zhen-xing Liu
    Abstract:

    Abstract The synthesis and crystal structure of two new complexes (Zn and Mn) containing tetrazolyl ligands are described. In situ [2+3] cycloaddition Reactions of fipronil, (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile) with sodium azide in the presence of ZnCl2 or MnCl2 as a Lewis acid (Demko–Sharpless tetrazole synthesis method) under hydrothermal (solvothermal) Reaction conditions gave [Zn(L)2](H2O)2] · H2O, 1 and [Mn(L)2](H2O)2] · H2O, 2, (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole). The central metals in both complexes are six coordinated, which connected by two water molecules, two nitrogen atoms from different tetrazolyl groups and two nitrogen atoms from pyrazolyl rings respectively. Photoluminescence studies reveal that both title complexes exhibit strong blue fluorescent emissions at λmax = 383 nm for 1 and 411 nm for 2 respectively in the solid state at room temperature.

  • Synthesis, crystal structures and luminescent properties of zinc and manganese complexes from Demko–Sharpless Reaction
    Inorganica Chimica Acta, 2009
    Co-Authors: Yun-zhi Tang, Yu-hui Tan, Dong-liang Liu, Xian-ping Luo, Xiao-bing Xie, Zhen-xing Liu
    Abstract:

    Abstract The synthesis and crystal structure of two new complexes (Zn and Mn) containing tetrazolyl ligands are described. In situ [2+3] cycloaddition Reactions of fipronil, (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile) with sodium azide in the presence of ZnCl2 or MnCl2 as a Lewis acid (Demko–Sharpless tetrazole synthesis method) under hydrothermal (solvothermal) Reaction conditions gave [Zn(L)2](H2O)2] · H2O, 1 and [Mn(L)2](H2O)2] · H2O, 2, (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole). The central metals in both complexes are six coordinated, which connected by two water molecules, two nitrogen atoms from different tetrazolyl groups and two nitrogen atoms from pyrazolyl rings respectively. Photoluminescence studies reveal that both title complexes exhibit strong blue fluorescent emissions at λmax = 383 nm for 1 and 411 nm for 2 respectively in the solid state at room temperature.

Tsutomu Katsuki - One of the best experts on this subject based on the ideXlab platform.

  • asymmetric epoxidation of allylic alcohols the katsuki Sharpless epoxidation Reaction
    Organic Reactions, 2004
    Co-Authors: Tsutomu Katsuki, Víctor S. Martín
    Abstract:

    In 1980, Sharpless and Katsuki discovered a system for the asymmetric epoxidation of primary allylic alcohols that utilizes Ti(OPr-i)4, a dialkyl tartrate as a chiral ligand, and tert-butyl hydroperoxide as the oxidant. Notably, this Reaction exhibits high levels of enantioselectivity (usually > 90% ee). Like other metal-catalyzed epoxidations, this Reaction also proceeds under mild conditions with good chemical yield and with high regio- and chemoselectivity. Various aspects of this Reaction, including its mechanism, early synthetic applications, and further transformations of the epoxy alcohol product, have been reviewed. In this chapter, the full scope and limitations of this Reaction, its synthetic applications, and typical experimental conditions are described. Keywords: epoxidation; allylic alcohols; Katsuki-Sharpless Reaction; titanium tartrate; mechanism; reactivity; stereoselectivity; chemiselectivity; regioselectivity; product stability; scope; limitations; asymmetric epoxidation. catalysts; primary allylic alcohols; secondary allylic alcohols; asymmetric oxidation; sulfides; selenides; amines; epoxy alcohols; transformations; functional units; Payne rearrangement; ring opening; kinetic resolution; chiral substrates; unfunctionalized olefins; synthesis; nonracemic epoxides; experimental conditions; experimental procedures; tabular survey

  • Organic Reactions - Asymmetric Epoxidation of Allylic Alcohols: the Katsuki–Sharpless Epoxidation Reaction
    Organic Reactions, 1996
    Co-Authors: Tsutomu Katsuki, Víctor S. Martín
    Abstract:

    In 1980, Sharpless and Katsuki discovered a system for the asymmetric epoxidation of primary allylic alcohols that utilizes Ti(OPr-i)4, a dialkyl tartrate as a chiral ligand, and tert-butyl hydroperoxide as the oxidant. Notably, this Reaction exhibits high levels of enantioselectivity (usually > 90% ee). Like other metal-catalyzed epoxidations, this Reaction also proceeds under mild conditions with good chemical yield and with high regio- and chemoselectivity. Various aspects of this Reaction, including its mechanism, early synthetic applications, and further transformations of the epoxy alcohol product, have been reviewed. In this chapter, the full scope and limitations of this Reaction, its synthetic applications, and typical experimental conditions are described. Keywords: epoxidation; allylic alcohols; Katsuki-Sharpless Reaction; titanium tartrate; mechanism; reactivity; stereoselectivity; chemiselectivity; regioselectivity; product stability; scope; limitations; asymmetric epoxidation. catalysts; primary allylic alcohols; secondary allylic alcohols; asymmetric oxidation; sulfides; selenides; amines; epoxy alcohols; transformations; functional units; Payne rearrangement; ring opening; kinetic resolution; chiral substrates; unfunctionalized olefins; synthesis; nonracemic epoxides; experimental conditions; experimental procedures; tabular survey