A three-dimensional coordination polymer [Mn2（μ1.3-N3）4（μ-PP）2]n （PP = 3-（pyrazin-2-yloxy）-pyridine） has been synthesized with 3-（pyrazin-2-yloxy）-pyridine and azide anion as mixed bridge ligand, and its c...A three-dimensional coordination polymer [Mn2（μ1.3-N3）4（μ-PP）2]n （PP = 3-（pyrazin-2-yloxy）-pyridine） has been synthesized with 3-（pyrazin-2-yloxy）-pyridine and azide anion as mixed bridge ligand, and its crystal structure was determined by X-ray crystallography. The crystal data： triclinic system, space group P1, with a = 6.794（4）, b = 9.885（6）, c = 9.947（6） A, α = 64.170（6）, β= 84.190（8）, γ= 85.319（8）°, V = 597.7（6）A^3, Z = 1, C18H14Mn2N18O2, Mr = 624.35, Dc = 1.735 g/cm^3, F（000） = 314 and μ = 1.117 mm^-1. In the crystal, the azide anion acts as a bridge ligand and makes adjacent Mn（Ⅱ） ions connect into a two-dimensional sheet on the ab plane, then 3-（pyrazin-2-yloxy）-pyridine serves as a bidentate bridge ligand to connect neighboring sheets along展开更多
An array of rare-earth bis(aminobenzyl)complexes supported by imidazolin-2-iminato ligands were synthesized and structurally characterized.These complexes showed high activity towards ortho-Csp^(2)–H alkylation of 2-...An array of rare-earth bis(aminobenzyl)complexes supported by imidazolin-2-iminato ligands were synthesized and structurally characterized.These complexes showed high activity towards ortho-Csp^(2)–H alkylation of 2-alkylpyridines and benzylic Csp^(3)–H alkylation of 2,6-dialkylpyridines with alkenes.A wide range of alkyl or aryl substituted olefin substrates are compatible,providing an atom-economical route to linear or branched alkylated pyridine derivatives in moderate to high yields(45 examples,up to 99%yield).The primary study suggested that the asymmetric version of Csp^(3)–H alkylation of 2,4,6-collidine with allylbenzene was feasible with chiral imidazolin-2-iminato-ligated scandium(III)complexes,and good yield with moderate enantioselectivity was obtained(84%yield,84:16 er).Mechanistic investigations including kinetic isotope effect(KIE)experiments and density functional theory(DFT)calculations shed light on the catalytic cycle and the origin of enantiocontrol.展开更多
A series of novel quinolinyl imidazolidin-2-imine nickel complexes with different substituents on the imidazolidin-2-imine ligand were synthesized and characterized.The complexes in the presence of methylaluminoxane(M...A series of novel quinolinyl imidazolidin-2-imine nickel complexes with different substituents on the imidazolidin-2-imine ligand were synthesized and characterized.The complexes in the presence of methylaluminoxane(MAO)as a cocatalyst catalyzed the copolymerization of norbornene(N)and styrene(S)or para-chlorostyrene(CS)with high activity(up to 1070 kg·mol^-1·h^-1).The installation of sterically bulky substituents on the imidazolidine-2-imine ligand was effective for the increase of the molecular weight and the comonomer content,affording high molecular weight copolymers with tunable CS content(0.57 mol%-11.7 mol%),in which the existence of CI group can provide reaction site for the further functionalization of copolymers as well as the synthesis of graft or cross-linked polymers.The linear relationship between the comonomer content and the glass transition temperature of the copolymers and the monomer reactivity ratios in the copolymerization indicated the formation of the expected functionalized cyclic olefin copolymers(COC).展开更多
基金Supported by the National Natural Science Foundation of China (No. 20271043)Natural Science Foundation of Shandong Province (Y2007B26)
文摘A three-dimensional coordination polymer [Mn2（μ1.3-N3）4（μ-PP）2]n （PP = 3-（pyrazin-2-yloxy）-pyridine） has been synthesized with 3-（pyrazin-2-yloxy）-pyridine and azide anion as mixed bridge ligand, and its crystal structure was determined by X-ray crystallography. The crystal data： triclinic system, space group P1, with a = 6.794（4）, b = 9.885（6）, c = 9.947（6） A, α = 64.170（6）, β= 84.190（8）, γ= 85.319（8）°, V = 597.7（6）A^3, Z = 1, C18H14Mn2N18O2, Mr = 624.35, Dc = 1.735 g/cm^3, F（000） = 314 and μ = 1.117 mm^-1. In the crystal, the azide anion acts as a bridge ligand and makes adjacent Mn（Ⅱ） ions connect into a two-dimensional sheet on the ab plane, then 3-（pyrazin-2-yloxy）-pyridine serves as a bidentate bridge ligand to connect neighboring sheets along
基金supported by the National Key R&D Program of China(2022YFA1504301)the National Natural Science Foundation of China(92056107,22271199,92256303,21890723)Sichuan University(2020SCUNL204)。
文摘An array of rare-earth bis(aminobenzyl)complexes supported by imidazolin-2-iminato ligands were synthesized and structurally characterized.These complexes showed high activity towards ortho-Csp^(2)–H alkylation of 2-alkylpyridines and benzylic Csp^(3)–H alkylation of 2,6-dialkylpyridines with alkenes.A wide range of alkyl or aryl substituted olefin substrates are compatible,providing an atom-economical route to linear or branched alkylated pyridine derivatives in moderate to high yields(45 examples,up to 99%yield).The primary study suggested that the asymmetric version of Csp^(3)–H alkylation of 2,4,6-collidine with allylbenzene was feasible with chiral imidazolin-2-iminato-ligated scandium(III)complexes,and good yield with moderate enantioselectivity was obtained(84%yield,84:16 er).Mechanistic investigations including kinetic isotope effect(KIE)experiments and density functional theory(DFT)calculations shed light on the catalytic cycle and the origin of enantiocontrol.
基金the National Natural Science Foundation of China(No.21774018)the Fundamental Research Funds for the Central Universities(No.2232020A-05)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning.
文摘A series of novel quinolinyl imidazolidin-2-imine nickel complexes with different substituents on the imidazolidin-2-imine ligand were synthesized and characterized.The complexes in the presence of methylaluminoxane(MAO)as a cocatalyst catalyzed the copolymerization of norbornene(N)and styrene(S)or para-chlorostyrene(CS)with high activity(up to 1070 kg·mol^-1·h^-1).The installation of sterically bulky substituents on the imidazolidine-2-imine ligand was effective for the increase of the molecular weight and the comonomer content,affording high molecular weight copolymers with tunable CS content(0.57 mol%-11.7 mol%),in which the existence of CI group can provide reaction site for the further functionalization of copolymers as well as the synthesis of graft or cross-linked polymers.The linear relationship between the comonomer content and the glass transition temperature of the copolymers and the monomer reactivity ratios in the copolymerization indicated the formation of the expected functionalized cyclic olefin copolymers(COC).
