The reaction of anhydrous YbCl3 with LiNPri2 in 1:3 molar ratio gave the homo- leptic lanthanide amide ate complex Yb(C6H14N)4Li(C4H8O). The crystal structure was determined by X-ray diffraction and the following crys...The reaction of anhydrous YbCl3 with LiNPri2 in 1:3 molar ratio gave the homo- leptic lanthanide amide ate complex Yb(C6H14N)4Li(C4H8O). The crystal structure was determined by X-ray diffraction and the following crystallographic data were obtained: C28H64N4OYbLi, Mg = 652.82, monoclinic, P21/c (#14), a = 15.239(3), b = 21.502(6), c = 21.288(4) ? b = 93.18(2), V = 6964(2) 3, Z = 8, Dc = 1.245 g/cm3, F(000) = 2728 and m(MoKa) = 27.08 cm-1. The final R and Rw are 0.044 and 0.053 for 6765 observed reflections with I > 3.00s(I), respectively. The ytterbium atom is bonded to two terminal amide ligands with the normal YbN distances of 2.171(6) and 2.174(7) ? and two bridging amide ligands with the YbN bonds about 0.1 ?longer than those of the formers, forming a distorted tetrahedral geometry.展开更多
The reaction of anhydrous YbCl3 with lithium b-diketiminate, LLi (L = N,N- diphenyl-2,4-pentanediimine anion), in 1:1 molar ratio in THF gave rise to the title complex LYbCl2(THF)2 1 which has been characterized by si...The reaction of anhydrous YbCl3 with lithium b-diketiminate, LLi (L = N,N- diphenyl-2,4-pentanediimine anion), in 1:1 molar ratio in THF gave rise to the title complex LYbCl2(THF)2 1 which has been characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pna21(#33) with a = 19.657(8), b = 9.581(4), c = 14.107(6) ? V = 2656.8(18) 3, Z = 4, C25H33N2O2Cl2Yb, Mr = 637.49, Dc = 1.594 g/cm3, F(000) = 1268.00 and m(MoKa) = 3.744mm-1. The final R and wR are 0.031 and 0.073 for 2596 observed reflections with I > 2s(I), respectively. The X-ray crystal structure analysis revealed that the center ytterbium(III) is bonded to two chloride anions, two oxygen atoms from two tetrahydrofuran molecules and one chelate ligand b-diketiminate to form a six-coordinate distorted octahedral geometry.展开更多
Ring opening polymerization of ε caprolactone was successfully carried out by diisopropylamido bis(methylcyclopentadienyl) erbium as catalyst. It is found that organoerbium amide is a very active catalyst for ε capr...Ring opening polymerization of ε caprolactone was successfully carried out by diisopropylamido bis(methylcyclopentadienyl) erbium as catalyst. It is found that organoerbium amide is a very active catalyst for ε caprolactone ring opening polymerization. The activity increases with the increasing of polymerization temperature. Under certain conditions, the polymerization system shows a living characteristic.展开更多
基金Supported by the National Natural Science Foundation of China (20072027) Department of Education of Jiangsu province and the Key Laboratory of Organic Synthesis of Jiangsu province
文摘The reaction of anhydrous YbCl3 with LiNPri2 in 1:3 molar ratio gave the homo- leptic lanthanide amide ate complex Yb(C6H14N)4Li(C4H8O). The crystal structure was determined by X-ray diffraction and the following crystallographic data were obtained: C28H64N4OYbLi, Mg = 652.82, monoclinic, P21/c (#14), a = 15.239(3), b = 21.502(6), c = 21.288(4) ? b = 93.18(2), V = 6964(2) 3, Z = 8, Dc = 1.245 g/cm3, F(000) = 2728 and m(MoKa) = 27.08 cm-1. The final R and Rw are 0.044 and 0.053 for 6765 observed reflections with I > 3.00s(I), respectively. The ytterbium atom is bonded to two terminal amide ligands with the normal YbN distances of 2.171(6) and 2.174(7) ? and two bridging amide ligands with the YbN bonds about 0.1 ?longer than those of the formers, forming a distorted tetrahedral geometry.
基金Supported by the National Natural Science Foundation of China (20072027) Department of Education of Jiangsu province and the Key Laboratory of Organic Synthesis of Jiangsu province
文摘The reaction of anhydrous YbCl3 with lithium b-diketiminate, LLi (L = N,N- diphenyl-2,4-pentanediimine anion), in 1:1 molar ratio in THF gave rise to the title complex LYbCl2(THF)2 1 which has been characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pna21(#33) with a = 19.657(8), b = 9.581(4), c = 14.107(6) ? V = 2656.8(18) 3, Z = 4, C25H33N2O2Cl2Yb, Mr = 637.49, Dc = 1.594 g/cm3, F(000) = 1268.00 and m(MoKa) = 3.744mm-1. The final R and wR are 0.031 and 0.073 for 2596 observed reflections with I > 2s(I), respectively. The X-ray crystal structure analysis revealed that the center ytterbium(III) is bonded to two chloride anions, two oxygen atoms from two tetrahydrofuran molecules and one chelate ligand b-diketiminate to form a six-coordinate distorted octahedral geometry.
文摘Ring opening polymerization of ε caprolactone was successfully carried out by diisopropylamido bis(methylcyclopentadienyl) erbium as catalyst. It is found that organoerbium amide is a very active catalyst for ε caprolactone ring opening polymerization. The activity increases with the increasing of polymerization temperature. Under certain conditions, the polymerization system shows a living characteristic.
