Ethylene trimerization toward 1-hexene catalytic system with 2,5-dimethylpyrrole （2,5-DMP）/Cr（III）/alkylaluminum/tetrachloroethane （TCE） was investigated. The effects of various cocatalysts on catalytic activity...Ethylene trimerization toward 1-hexene catalytic system with 2,5-dimethylpyrrole （2,5-DMP）/Cr（III）/alkylaluminum/tetrachloroethane （TCE） was investigated. The effects of various cocatalysts on catalytic activity and product selectivity were discussed. The results showed that triethylaluminum （TEA）, trimethylaluminum （TMA）, tri-n-hexylaluminum （TNHA） and tri-isobutylaluminum （TIBA） were all effective cocatalysts for ethylene trimerization toward 1-hexene. 2,5-DMP/Cr（III）/TEA/TCE catalytic system afforded the best results for ethylene trimerization, while reducing the level of by-product formation. Some specific interaction modes of alkylaluminum with active Cr species in the catalytic cycle were proposed to explain the effect of cocatalyst on catalytic activity and 1-hexene selectivity.展开更多
Two coordination compounds [Pb4（BDT）3（OH）2（H2O）4].H2O （1） and [Mn（H20）6]·（HBDT）2.2H2O （2） [H2BDT= 5,5＇-（1,4-phenylene）bis（1H-tetrazole）] had been hydrothermally synthesized. 1 and 2 had been ch...Two coordination compounds [Pb4（BDT）3（OH）2（H2O）4].H2O （1） and [Mn（H20）6]·（HBDT）2.2H2O （2） [H2BDT= 5,5＇-（1,4-phenylene）bis（1H-tetrazole）] had been hydrothermally synthesized. 1 and 2 had been characterized by single-crystal X-ray diffraction, IR, elemental and thermal analyses. Structural analysis reveals that 1 exhibits 2D layer structure extended through BDT with two different coordination modes rings in transverse and vertical. 2 consists of [Mn（H2O）6]2＋, free HBDT and water. In addition, 1 and 2 were explored as luminescent materials and additives to promote the thermal decomposition of ammonium perchlorate by differential scanning calorimetry.展开更多
TBAJ-876, developed by TB Alliance, a novel anti-tuberculosis-specific drug, has entered Phase II clinical trials. Herein, the first asymmetric synthesis of TBAJ-876 has been realized using synergistic Li/Li catalysis...TBAJ-876, developed by TB Alliance, a novel anti-tuberculosis-specific drug, has entered Phase II clinical trials. Herein, the first asymmetric synthesis of TBAJ-876 has been realized using synergistic Li/Li catalysis with excellent yield of 95% and 88 : 12 er (99.6 : 0.4 er, 10 : 1 dr after simple recrystallization). Furthermore, DFT calculations and 7Li-NMR analysis illustrated the mechanism of the synergistic reaction: a chiral Li-complex activates the nucleophile to control the stereoselectivity, while the other achiral Li-complex activates the electrophile to catalyze the carbonyl addition reaction. Additionally, this protocol has been successfully carried out at 5 gram-scale, showing its industrial potential.展开更多
The hydrothermal reactions of Ni（Ⅱ）, 1,2,3-benzenetricarboxylic acid （1,2,3-H3btc） and 4,4＇-bipyfidine （4,4＇-bpy）/1,2-bis（4-pyridyl）ethane （bpa） yield two layered nickel（II） coordination polymers, [Ni2...The hydrothermal reactions of Ni（Ⅱ）, 1,2,3-benzenetricarboxylic acid （1,2,3-H3btc） and 4,4＇-bipyfidine （4,4＇-bpy）/1,2-bis（4-pyridyl）ethane （bpa） yield two layered nickel（II） coordination polymers, [Ni2（l,2,3-btc）（OAc）- （4,4＇-bpy）2（H20）]o2H2O （1） and [Ni（ip）（bpa）] （2） （ip=isophthalate）, respectively. Both complexes are 2-D coordi- nation network based on 1-D Ni-carboxylate chains. The 1,2,3-btc ligand adopts 3-bridging mode in complex 1, but transformed to isophthalate （ip） ligand through decarboxylation in 2. The formation of the two complexes indicates that hydrothermal conditions and in-situ ligand reaction have significant effect on constructing coordination polymers.展开更多
The reaction of DyCl_(3)·6H_(2)O with a rigid diacylhydrazone ligand(H_(2)L)afforded a trinuclear precursor[Dy_(3)L_(2)Cl_(3)(H_(2)O)_(2)(CH_(3)OH)]Cl_(2)·3CH_(3)OH(1).The replacement of the Cl-ions and the ...The reaction of DyCl_(3)·6H_(2)O with a rigid diacylhydrazone ligand(H_(2)L)afforded a trinuclear precursor[Dy_(3)L_(2)Cl_(3)(H_(2)O)_(2)(CH_(3)OH)]Cl_(2)·3CH_(3)OH(1).The replacement of the Cl-ions and the coordinating solvents by the aryloxides ligands(Lx)-yields three trinuclear complexes[Dy_(3)L_(2)(Lx)_(5)]·nsol(x=1,2-naphthol(2);x=2,7-hydroxycoumarin(3);and x=3,phenol(4)).In complexes 2-4,two end Dy^(3+)centers adopt almost identical N_(4)O_(4) coordination sphere of D6h geometry while the central one adopts N_(4)O_(5) coordination sphere in Cs geometry.Magnetic measurements reveal weak antiferromagnetic interactions in the hydrated samples 2e-4e and two-step slow relaxation process under zero dc field with effective energy barriers Ueff of 439 and 91 K,353 and 40 K,466 and 89 K for SR and FR in 2e-4e,respectively.Such dynamic magnetic behaviour for 4 persists in the magnetically diluted sample of 4@Y.Complex 4 possesses the short Dy-O_(aryloxide) bond distance of 2.055(18)Å,and the largest Ueff among the reported linear trinuclear dysprosium complexes.Moreover,the functionalized aryloxides ligands(Lx)-show photoluminescence via intramolecular energy transfer,making 2e-4e luminescent Dy^(3+)SMMs with high energy barriers.展开更多
In the information-explosion era,developing novel algorithms and memristive devices has become a promising concept for next-generation capacity enlargement technology.Organic small molecule-based devices displaying su...In the information-explosion era,developing novel algorithms and memristive devices has become a promising concept for next-generation capacity enlargement technology.Organic small molecule-based devices displaying superior learning-memory performance have attracted much attention,except for the existence of poor heat-resilience and mediocre conductivity.In this paper,a strategy of transforming an organic-type data-storage material to metal complex is proposed to resolve these intrinsic issues.A pristine NDI-derivative(NIPy)and its corresponding Co(II)complex(CoNIPy)are synthesized for the purpose of electrical property investigation.CoNIPy complex-based memristive device exhibits superior ternary WORM memory performance compared with the binary behavior of NIPy,including>104 s of reading,lower threshold voltage(V_(th)),1:10^(2):10^(5)of OFF/ON1/ON2 current ratio,and long-term stability in heating environment.The variable learning-memory behavior can be attributed to the enhanced ligand-to-metal charge transfer(LMCT)and improved redox activity after the introduction of central metal atom and coordination bond.These studies on material innovation and optimal performance are of great importance not only for environmentally-robust memristive devices but also for practical application of a host of organic electronic devices.展开更多
基金Project supported by the Program for New Century Excelleni Talents in University （No. NCET-07-0142）, the Program for New Century Excellent Talents in Heilongjiang Provincial University （No. NCET-06-010）, the National Natural Science Foundation of China （No. 20972025） and the Science Foundation of Tianjin University of Science ＆ Technology （No. 20090420）.
文摘Ethylene trimerization toward 1-hexene catalytic system with 2,5-dimethylpyrrole （2,5-DMP）/Cr（III）/alkylaluminum/tetrachloroethane （TCE） was investigated. The effects of various cocatalysts on catalytic activity and product selectivity were discussed. The results showed that triethylaluminum （TEA）, trimethylaluminum （TMA）, tri-n-hexylaluminum （TNHA） and tri-isobutylaluminum （TIBA） were all effective cocatalysts for ethylene trimerization toward 1-hexene. 2,5-DMP/Cr（III）/TEA/TCE catalytic system afforded the best results for ethylene trimerization, while reducing the level of by-product formation. Some specific interaction modes of alkylaluminum with active Cr species in the catalytic cycle were proposed to explain the effect of cocatalyst on catalytic activity and 1-hexene selectivity.
基金Project supported by the National Natural Science Foundation of China （No. 20873100）, and the Natural Science Foundation of Shaanxi Province （Nos. FF10091, SJ08B09）.
文摘Two coordination compounds [Pb4（BDT）3（OH）2（H2O）4].H2O （1） and [Mn（H20）6]·（HBDT）2.2H2O （2） [H2BDT= 5,5＇-（1,4-phenylene）bis（1H-tetrazole）] had been hydrothermally synthesized. 1 and 2 had been characterized by single-crystal X-ray diffraction, IR, elemental and thermal analyses. Structural analysis reveals that 1 exhibits 2D layer structure extended through BDT with two different coordination modes rings in transverse and vertical. 2 consists of [Mn（H2O）6]2＋, free HBDT and water. In addition, 1 and 2 were explored as luminescent materials and additives to promote the thermal decomposition of ammonium perchlorate by differential scanning calorimetry.
基金funding support of this work by the Bill and Melinda Gates Foundation(No.INV-008413)the National Natural Science Foundation of China(No.21831005)and Shanghai Jiao Tong University.
文摘TBAJ-876, developed by TB Alliance, a novel anti-tuberculosis-specific drug, has entered Phase II clinical trials. Herein, the first asymmetric synthesis of TBAJ-876 has been realized using synergistic Li/Li catalysis with excellent yield of 95% and 88 : 12 er (99.6 : 0.4 er, 10 : 1 dr after simple recrystallization). Furthermore, DFT calculations and 7Li-NMR analysis illustrated the mechanism of the synergistic reaction: a chiral Li-complex activates the nucleophile to control the stereoselectivity, while the other achiral Li-complex activates the electrophile to catalyze the carbonyl addition reaction. Additionally, this protocol has been successfully carried out at 5 gram-scale, showing its industrial potential.
基金Project supported by the National Natural Science Foundation of China （No. 20901018） and Natural Science Foundations of Guangdong Province （No. 9451009101003177）.
文摘The hydrothermal reactions of Ni（Ⅱ）, 1,2,3-benzenetricarboxylic acid （1,2,3-H3btc） and 4,4＇-bipyfidine （4,4＇-bpy）/1,2-bis（4-pyridyl）ethane （bpa） yield two layered nickel（II） coordination polymers, [Ni2（l,2,3-btc）（OAc）- （4,4＇-bpy）2（H20）]o2H2O （1） and [Ni（ip）（bpa）] （2） （ip=isophthalate）, respectively. Both complexes are 2-D coordi- nation network based on 1-D Ni-carboxylate chains. The 1,2,3-btc ligand adopts 3-bridging mode in complex 1, but transformed to isophthalate （ip） ligand through decarboxylation in 2. The formation of the two complexes indicates that hydrothermal conditions and in-situ ligand reaction have significant effect on constructing coordination polymers.
基金This work was supported by the National Natural Science Foundation of China(21971142,21973046 and 22271171).
文摘The reaction of DyCl_(3)·6H_(2)O with a rigid diacylhydrazone ligand(H_(2)L)afforded a trinuclear precursor[Dy_(3)L_(2)Cl_(3)(H_(2)O)_(2)(CH_(3)OH)]Cl_(2)·3CH_(3)OH(1).The replacement of the Cl-ions and the coordinating solvents by the aryloxides ligands(Lx)-yields three trinuclear complexes[Dy_(3)L_(2)(Lx)_(5)]·nsol(x=1,2-naphthol(2);x=2,7-hydroxycoumarin(3);and x=3,phenol(4)).In complexes 2-4,two end Dy^(3+)centers adopt almost identical N_(4)O_(4) coordination sphere of D6h geometry while the central one adopts N_(4)O_(5) coordination sphere in Cs geometry.Magnetic measurements reveal weak antiferromagnetic interactions in the hydrated samples 2e-4e and two-step slow relaxation process under zero dc field with effective energy barriers Ueff of 439 and 91 K,353 and 40 K,466 and 89 K for SR and FR in 2e-4e,respectively.Such dynamic magnetic behaviour for 4 persists in the magnetically diluted sample of 4@Y.Complex 4 possesses the short Dy-O_(aryloxide) bond distance of 2.055(18)Å,and the largest Ueff among the reported linear trinuclear dysprosium complexes.Moreover,the functionalized aryloxides ligands(Lx)-show photoluminescence via intramolecular energy transfer,making 2e-4e luminescent Dy^(3+)SMMs with high energy barriers.
基金Y.L.thanks financial support from the National Natural Science Foundation of China(Grants No.22008164)the Natural Science Foundation of Jiangsu Province(Grants No.BK20190939)+4 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(Grants No.19KJB150018)This work is also supported by Six Talent Peaks Project of Jiangsu Province,China(XCL-078)Jiangsu Key Disciplines of the Fourteenth Five-Year Plan(2021135)the Suzhou Key Laboratory for Low Dimensional Optoelectronic Materials and Devices(SzS201611)Q.Z.thanks thefunding support from City University of Hong Kong(9380117,7005620 and 7020040)and Hong Kong Institute for Advanced Study,City University of Hong Kong,Hong Kong,P.R.China.
文摘In the information-explosion era,developing novel algorithms and memristive devices has become a promising concept for next-generation capacity enlargement technology.Organic small molecule-based devices displaying superior learning-memory performance have attracted much attention,except for the existence of poor heat-resilience and mediocre conductivity.In this paper,a strategy of transforming an organic-type data-storage material to metal complex is proposed to resolve these intrinsic issues.A pristine NDI-derivative(NIPy)and its corresponding Co(II)complex(CoNIPy)are synthesized for the purpose of electrical property investigation.CoNIPy complex-based memristive device exhibits superior ternary WORM memory performance compared with the binary behavior of NIPy,including>104 s of reading,lower threshold voltage(V_(th)),1:10^(2):10^(5)of OFF/ON1/ON2 current ratio,and long-term stability in heating environment.The variable learning-memory behavior can be attributed to the enhanced ligand-to-metal charge transfer(LMCT)and improved redox activity after the introduction of central metal atom and coordination bond.These studies on material innovation and optimal performance are of great importance not only for environmentally-robust memristive devices but also for practical application of a host of organic electronic devices.
