A series of blue luminescent zinc(II) complexes, [Zn(dpa)X2] [dpa = di-2-pyridylamine, X = OAc 1a, Cl 1b, CN 1c or 4-MeC6H4S 1d], [Zn(dpa)2][CF3SO3]2 2, [Zn(tpda)X2] [tpda = 2,6-bis(2-pyridylamino)pyridine, X = OAc 3a or Cl 3b] and [Zn(tpda)(CF3SO3)2] 4 has been prepared. Their molecular structures, except complex 4, have been established by X-ray crystallography. In the crystal lattice of 2 the [Zn(dpa)2]2+ cations and CF3SO3– anions are disposed in pairs via intermolecular hydrogen bonds [N(2)· · ·O(2) 2.865(4) Å]. The crystal packing of [Zn(dpa)(OAc)2] 1a revealed that two adjacent molecules associate in pairs through intermolecular hydrogen bonding [N(2)· · ·O(4′) 2.816(3) Å]. However, the crystal lattice of its tpda derivative 3a shows that the molecules are linked by extensive intermolecular hydrogen bonding between the amino groups and the acetate ligands [N(2)· · ·O(2′) 2.805(3) and N(4)· · ·O(4′) 2.860(3) Å] resulting in an interlocking hydrogen bond network. Polymeric one-dimensional tapes are generated through extended π–π stacking interactions between the molecules of [Zn(dpa)(4-MeC6H4S)2] 1d, and the thiolate groups are aligned in an all-anti conformation along the metal chain. In the case of [Zn(dpa)(CN)2] 1c, co-operative intermolecular hydrogen bonds and aromatic π–π interactions in its solid state lead to a supramolecular two-dimensional sheet. All the zinc(II) complexes display high energy intraligand 1(π–π*) fluorescence in degassed MeOH at 298 K, and intraligand 3(π–π*) phosphorescence in a glassy solution (MeOH–EtOH 1∶2 at 77 K). An emission band observed for 1c (418 nm) and 1d (481 nm) in their solid state emission spectra is ascribed to excimeric emission due to aromatic π–π interactions.
一系列蓝色发光
锌(II)配合物 [Zn(dpa)X2] [dpa = 二-2-
吡啶基胺,X = OAc 1a、Cl 1b、CN 1c 或 4-MeC6H4S 1d]、制备了[Zn(dpa)2][CF3SO3]2 2、[Zn(tpda)X2][tpda = 2,6-双(2-
吡啶氨基)
吡啶,X = OAc 3a 或 Cl 3b]和[Zn(tpda)(CF3SO3)2] 4。除复合物 4 外,它们的分子结构均已通过 X 射线晶体学确定。在 2 的晶格中,[Zn(dpa)2]2+ 阳离子和 CF3SO3- 阴离子通过分子间氢键[N(2)- -O(2) 2.865(4) Å]成对排列。Zn(dpa)(OAc)2] 1a 的晶体堆积显示,相邻的两个分子通过分子间氢键[N(2)- -O(4′) 2.816(3) Å]成对结合。然而,其 tpda 衍
生物 3a 的晶格显示,分子之间通过
氨基和
醋酸配体之间广泛的分子间氢键[N(2)- -O(2′) 2.805(3)埃和 N(4)- -O(4′) 2.860(3)埃]连接在一起,形成了一个交错的氢键网络。通过[Zn(dpa)(4-MeC6H4S)2] 1d 分子间扩展的 π-π 堆叠相互作用生成了聚合物一维带,
硫醇基沿着
金属链以全反构象排列。至于[Zn(dpa)(CN)2] 1c,其固态中分子间的氢键和芳香族的π-π相互作用导致了超分子二维薄片。所有
锌(II)配合物在 298 K 的脱气 MeOH 中都显示出高能量的配位体内部 1(π-π*)荧光,在
玻璃溶液(77 K 时 MeOH-EtOH 1∶2)中显示出配位体内部 3(π-π*)
磷光。在固态发射光谱中观察到的 1c(418 纳米)和 1d(481 纳米)发射带是由于芳香族 π-π 相互作用而产生的准分子发射。