An efficient electrochemical access to the non-symmetric biphenols using tri(p-bromophenyl)amine(TBPA)as a redox mediator has been developed.The electrochemical protocol features highly selective cross-coupling produc...An efficient electrochemical access to the non-symmetric biphenols using tri(p-bromophenyl)amine(TBPA)as a redox mediator has been developed.The electrochemical protocol features highly selective cross-coupling products in up to 83% yield,instead of forming homo-coupling ones.展开更多
Anhydrous EuCl3 reacted with sodium carbon-bridged biphenolate LNa2[ L = 2,2'-methylene bis(6-tert-butyl-4- methyl-phenoxo ] in a 1 : 1 molar ratio in THF in the presence of HMPA (HMPA = hexamethylphosphoric triam...Anhydrous EuCl3 reacted with sodium carbon-bridged biphenolate LNa2[ L = 2,2'-methylene bis(6-tert-butyl-4- methyl-phenoxo ] in a 1 : 1 molar ratio in THF in the presence of HMPA (HMPA = hexamethylphosphoric triamide), then the product formed in situ was reduced by Na-K alloy to generate the divalent carbon-bridged biphenolate europium complex [ LEu (HMPA) 2 ] 2 (THF) 4 ( 1 ) in a good isolated yield. Complex 1 was fully characterized by elemental analysis, NMR and IR spectra, and X-ray structural determination. The crystal data of complex 1 are monoclinic, P2 1/c space group, a=1.6521(3) nm, b=2.8274(3) nm, c=1.2074(2) nm, β=111.723(6)°, V=5.2393(14) nm^3, Z=2, Dc= 1.259 mg·m^-3, μ = 1.304 mm^-1, F(000) = 2092, R = 0.0815, wR = 0. 1723. Complex 1 is a dimer with two Eu - O bridges. The coordination geometry of each europium atom can be best described as a distorted trigonal bipyramid.展开更多
A novel phosphonate-based chiral metal-organic framework 1 was synthesized from C2-symmetric 1,1?-biphenol-based ligand and structurally characterized by single-crystal and powder X-ray diffraction, Fourier-transform...A novel phosphonate-based chiral metal-organic framework 1 was synthesized from C2-symmetric 1,1?-biphenol-based ligand and structurally characterized by single-crystal and powder X-ray diffraction, Fourier-transform infrared spectra(FTIR), circular dichroism(CD) and thermogravimetric analyses(TGA). Two neighboring Mn ions are linked by two carboxylate groups and one phosphate group to form a di-manganese unit [Mn2] and each [Mn2] cluster in 1 is linked by five ligands, generating a 3D network with fns topology. In addition, the photoluminescence properties of 1 and H4 L were investigated.展开更多
Discrete ion-pair complexes [Ln(EDBP)2(DME)Na(DME)3] [Ln=Er (1), Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2,2'-ethylidene-bis(4,6-di-tert-butylphenol)(EDBPH2) and Ln(BH4)3·...Discrete ion-pair complexes [Ln(EDBP)2(DME)Na(DME)3] [Ln=Er (1), Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2,2'-ethylidene-bis(4,6-di-tert-butylphenol)(EDBPH2) and Ln(BH4)3·3THF (Ln=Er, Yb, Sm) followed by centrifugation and recrystalization. The complexes were characterized by elemental analysis and FT-IR, and the bonding model of these compounds was confirmed by X-ray single crystal diffraction for complex 1. It was found that four O atoms in two biphenol ligands as well as two O atoms in one ethylene glycol dimethyl ether (DME) molecule connect to the center rare earth metal atom, while sodium exists as counterpart cation to balance the charge. Complexes 1―3 can all be used as single component initiators for the ring-opening polymerization of ε-caprolactone.展开更多
The biphenol based discrete ion-pair rare earth complexes, [Ln(EDBP)2(DME)Na(DME)3] [Ln = Er(1), Yb(2), Sm(3)], were prepared and used as catalysts for the ring-opening polymerization (ROP) of 2,2-dimeth...The biphenol based discrete ion-pair rare earth complexes, [Ln(EDBP)2(DME)Na(DME)3] [Ln = Er(1), Yb(2), Sm(3)], were prepared and used as catalysts for the ring-opening polymerization (ROP) of 2,2-dimethyltrimethylene carbonate (DTC). Three complexes show moderate activities for the polymerization, and the catalytic activities increase in the following sequence: (Yb 〈 Er 〈 Sm). The effect of different ratios of [DTC]/[Ln], polymerization temperature and time on the polymerization was investigated. Moreover, PDTC without ether unit developed from possible CO2 elimination was prepared.展开更多
基金grants from the National Key Technology R&D Program(No.2016YFD0400801)the National Natural Science Foundation of China(No.21871019).
文摘An efficient electrochemical access to the non-symmetric biphenols using tri(p-bromophenyl)amine(TBPA)as a redox mediator has been developed.The electrochemical protocol features highly selective cross-coupling products in up to 83% yield,instead of forming homo-coupling ones.
文摘Anhydrous EuCl3 reacted with sodium carbon-bridged biphenolate LNa2[ L = 2,2'-methylene bis(6-tert-butyl-4- methyl-phenoxo ] in a 1 : 1 molar ratio in THF in the presence of HMPA (HMPA = hexamethylphosphoric triamide), then the product formed in situ was reduced by Na-K alloy to generate the divalent carbon-bridged biphenolate europium complex [ LEu (HMPA) 2 ] 2 (THF) 4 ( 1 ) in a good isolated yield. Complex 1 was fully characterized by elemental analysis, NMR and IR spectra, and X-ray structural determination. The crystal data of complex 1 are monoclinic, P2 1/c space group, a=1.6521(3) nm, b=2.8274(3) nm, c=1.2074(2) nm, β=111.723(6)°, V=5.2393(14) nm^3, Z=2, Dc= 1.259 mg·m^-3, μ = 1.304 mm^-1, F(000) = 2092, R = 0.0815, wR = 0. 1723. Complex 1 is a dimer with two Eu - O bridges. The coordination geometry of each europium atom can be best described as a distorted trigonal bipyramid.
基金Supported by NSFC(No.21431004,21522104 and 21620102001)“973”Program(No.2014CB932102 and 2016YFA0203400)+1 种基金the Shanghai“Eastern Scholar”Program SSTC-14YF1401300the Key Project of Basic Research of Shanghai(17JC1403100)
文摘A novel phosphonate-based chiral metal-organic framework 1 was synthesized from C2-symmetric 1,1?-biphenol-based ligand and structurally characterized by single-crystal and powder X-ray diffraction, Fourier-transform infrared spectra(FTIR), circular dichroism(CD) and thermogravimetric analyses(TGA). Two neighboring Mn ions are linked by two carboxylate groups and one phosphate group to form a di-manganese unit [Mn2] and each [Mn2] cluster in 1 is linked by five ligands, generating a 3D network with fns topology. In addition, the photoluminescence properties of 1 and H4 L were investigated.
基金Supported by the National Natural Science Foundation of China (Grant No. 20376085)the Major State Basic Research Program of China (Grant No. 2005CB623800)
文摘Discrete ion-pair complexes [Ln(EDBP)2(DME)Na(DME)3] [Ln=Er (1), Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2,2'-ethylidene-bis(4,6-di-tert-butylphenol)(EDBPH2) and Ln(BH4)3·3THF (Ln=Er, Yb, Sm) followed by centrifugation and recrystalization. The complexes were characterized by elemental analysis and FT-IR, and the bonding model of these compounds was confirmed by X-ray single crystal diffraction for complex 1. It was found that four O atoms in two biphenol ligands as well as two O atoms in one ethylene glycol dimethyl ether (DME) molecule connect to the center rare earth metal atom, while sodium exists as counterpart cation to balance the charge. Complexes 1―3 can all be used as single component initiators for the ring-opening polymerization of ε-caprolactone.
基金supported by the National Natural Science Foundation(No.20674071)the Special Funds for Major State Basic Research Projects(No.2005CB623802)
文摘The biphenol based discrete ion-pair rare earth complexes, [Ln(EDBP)2(DME)Na(DME)3] [Ln = Er(1), Yb(2), Sm(3)], were prepared and used as catalysts for the ring-opening polymerization (ROP) of 2,2-dimethyltrimethylene carbonate (DTC). Three complexes show moderate activities for the polymerization, and the catalytic activities increase in the following sequence: (Yb 〈 Er 〈 Sm). The effect of different ratios of [DTC]/[Ln], polymerization temperature and time on the polymerization was investigated. Moreover, PDTC without ether unit developed from possible CO2 elimination was prepared.