Department of Chemistry, Kent State University-Salem, Salem, Ohio 44460, USA.
Inorg Chem. 2012 Mar 5;51(5):3270-82. doi: 10.1021/ic202732k. Epub 2012 Feb 17.
Reactions between 2,6-diformyl-4-methylphenol (DFMF) and tris(hydroxymethyl) aminomethane (THMAM = H(3)L2) in the presence of copper(II) salts, CuX(2) (X = CH(3)CO(2)(-), BF(4)(-), ClO(4)(-), Cl(-), NO(3)(-)) and Ni(CH(3)CO(2))(2) or Ni(ClO(4))(2)/NaC(6)H(5)CO(2), sodium azide (NaN(3)), and triethylamine (TEA), in one pot self-assemble giving a coordination polymer consisting of repeating pentanuclear copper(II) clusters {Cu(2)(H(5)L(2-))(μ-N(3))[Cu(N(3))(4)]·2CH(3)OH}(n) (1) and hexanuclear Ni(II) complexes [Ni(6)(H(3)L1(-))(2)(HL2(2-))(2)(μ-N(3))(4)(CH(3)CO(2))(2)]·6C(3)H(7)NO·C(2)H(5)OH (2) and [Ni(6)(H(3)L1(-))(2)(HL2(2-))(2)(μ-N(3))(4)(C(6)H(5)CO(2))(2)]·3C(3)H(7)NO·3H(2)O·CH(3)OH (3). In 1, H(5)L(2-) and in 2 and 3 H(3)L1(-) and HL2(2-) represent doubly deprotonated, singly deprotonated, and doubly deprotonated Schiff-base ligands H(7)L and H(4)L1 and a tripodal ligand H(3)L2, respectively. 1 has a novel double-stranded ladder-like structure in which Cu(N(3))(4) anions link single chains comprised of dinuclear cationic subunits Cu(2)(H(5)L(2-))(μ-N(3)), forming a 3D structure of interconnected ladders through H bonding. Nickel(II) clusters 2 and 3 have very similar neutral hexanuclear cores in which six nickel(II) ions are bonded to two H(4)L1, two H(3)L2, four μ-azido, and two μ-CH(3)CO(2)(-)/μ-C(6)H(5)CO(2)(-) ligands. In each structure two terminal dinickel (Ni(2)) units are connected to the central dinickel unit through four doubly bridging end-on (EO) μ-azido and four triply bridging μ(3)-methoxy bridges organizing into hexanuclear units. In each terminal dinuclear unit two nickel centers are bridged through one μ-phenolate oxygen from H(3)L1(-), one μ(3)-methoxy oxygen from HL2(2-), and one μ-CH(3)CO(2)(-) (2)/μ-C(6)H(5)CO(2)(-) (3) ion. Bulk magnetization measurements on 1 show moderately strong antiferromagnetic coupling within the [Cu(2)] building block (J(1) = -113.5 cm(-1)). Bulk magnetization measurements on 2 and 3 demonstrate that the magnetic interactions are completely dominated by ferromagnetic coupling occurring between Ni(II) ions for all bridges with coupling constants (J(1), J(2), and J(3)) ranging from 2.10 to 14.56 cm(-1) (in the Ĥ = -J(1)(Ŝ(1)Ŝ(2)) - J(1)(Ŝ(2)Ŝ(3)) - J(2)(Ŝ(3)Ŝ(4)) - J(1)(Ŝ(4)Ŝ(5)) - J(1)(Ŝ(5)Ŝ(6)) - J(2)(Ŝ(1)Ŝ(6)) - J(3)(Ŝ(2)Ŝ(6)) - J(3)(Ŝ(2)Ŝ(5)) - J(3)(Ŝ(3)Ŝ(5)) convention).
2,6-二醛基-4-甲基苯酚（DFMF）与三羟甲基氨基甲烷（THMAM = H(3)L2）在铜（II）盐存在下的反应，CuX(2)（X = CH(3)CO(2)(-)，BF(4)(-)，ClO(4)(-)，Cl(-)，NO(3)(-)）和 Ni(CH(3)CO(2))(2)或 Ni(ClO(4))(2)/NaC(6)H(5)CO(2)，叠氮化钠（NaN(3)）和三乙胺（TEA），一锅自组装形成由重复的五核铜（II）簇组成的配位聚合物{Cu(2)(H(5)L(2-))(μ-N(3))[Cu(N(3))(4)]·2CH(3)OH}(n)（1）和六核镍（II）配合物[Ni(6)(H(3)L1(-))(2)(HL2(2-))(2)(μ-N(3))(4)(CH(3)CO(2))(2)]·6C(3)H(7)NO·C(2)H(5)OH（2）和[Ni(6)(H(3)L1(-))(2)(HL2(2-))(2)(μ-N(3))(4)(C(6)H(5)CO(2))(2)]·3C(3)H(7)NO·3H(2)O·CH(3)OH（3）。在 1 中，H(5)L(2-)和在 2 和 3 中，H(3)L1(-)和 HL2(2-)分别代表双脱质子、单脱质子和双脱质子希夫碱配体 H(7)L 和 H(4)L1 和三齿配体 H(3)L2。1 具有新颖的双链梯状结构，其中Cu(N(3))(4)阴离子连接由二核阳离子亚基Cu(2)(H(5)L(2-))(μ-N(3))组成的单链，通过氢键形成相互连接的梯状 3D 结构。镍（II）配合物 2 和 3 具有非常相似的中性六核核芯，其中六个镍（II）离子与两个 H(4)L1、两个 H(3)L2、四个μ-叠氮和两个μ-CH(3)CO(2)(-) /μ-C(6)H(5)CO(2)(-)配体结合。在每个结构中，两个末端二镍（Ni(2))单元通过四个端接（EO）μ-叠氮和四个三桥μ-甲氧基桥连接到中心二镍单元，将其组织成六核单元。在每个末端二核单元中，两个镍中心通过 H(3)L1(-)中的一个μ-苯酚氧、HL2(2-)中的一个μ(3)-甲氧基氧和一个μ-CH(3)CO(2)(-)（2）/μ-C(6)H(5)CO(2)(-)（3）离子桥接。对 1 的体磁化率测量表明，在[Cu(2)]构建块内存在中等强度的反铁磁耦合（J(1) = -113.5 cm(-1)）。对 2 和 3 的体磁化率测量表明，磁相互作用完全由所有桥接物之间的铁磁耦合主导，对于所有桥接物，耦合常数（J(1)，J(2)和 J(3))范围从 2.10 到 14.56 cm(-1)（在Ĥ = -J(1)(Ŝ(1)Ŝ(2)) - J(1)(Ŝ(2)Ŝ(3)) - J(2)(Ŝ(3)Ŝ(4)) - J(1)(Ŝ(4)Ŝ(5)) - J(1)(Ŝ(5)Ŝ(6)) - J(2)(Ŝ(1)Ŝ(6)) - J(3)(Ŝ(2)Ŝ(6)) - J(3)(Ŝ(2)Ŝ(5)) - J(3)(Ŝ(3)Ŝ(5)) 约定）。
