Chandrasekhar Vadapalli, Azhakar Ramachandran, Senthil Andavan Gurusamy Thanagavelu, Krishnan Venkatasubbaiah, Zacchini Stefano, Bickley Jamie F, Steiner Alexander, Butcher Raymond J, Kögerler Paul
Department of Chemistry, Indian Institute of Technology, Kanpur-208 016, India.
Inorg Chem. 2003 Sep 22;42(19):5989-98. doi: 10.1021/ic034434h.
A phosphorus supported multisite coordinating ligand P(S)N(Me)N=CH-C(6)H(4)-o-OH (2) was prepared by the condensation of the phosphorus tris hydrazide P(S)N(Me)NH(2) (1) with o-hydroxybenzaldehyde. The reaction of 2 with M(OAc)(2).xH(2)O (M = Mn, Co, Ni, x = 4; M = Zn, x = 2) afforded neutral trinuclear complexes P(S)N(Me)N=CH-C(6)H(4)-o-OM(3) [M = Mn (3), Co (4), Ni (5), and Zn (6)]. The X-ray crystal structures of compounds 2-6 have been determined. The structures of 3-6 reveal that the trinculear metal assemblies are nearly linear. The two terminal metal ions in a given assembly have an N(3)O(3) ligand environment in a distorted octahedral geometry while the central metal ion has an O(6) ligand environment also in a slightly distorted octahedral geometry. In all the complexes, ligand 2 coordinates to the metal ions through three imino nitrogens and three phenolate oxygens; the latter act as bridging ligands to connect the terminal and central metal ions. The compounds 2-6 also show intermolecular C-H...S=P contacts in the solid-state which lead to the formation of polymeric supramolecular architectures. The observed magnetic data for the (s = 5/2)3 L(2)(Mn(II))(3) derivative, 3, show an antiferromagnetic nearest- and next-nearest-neighbor exchange (J = -4.0 K and J' = -0.15 K; using the spin Hamiltonian H(HDvV) = -2J(S(1)S(2) + S(2)S(3)) - 2J'S(1)S(3)). In contrast, the (s = 1)(3) L(2)(Ni(II))(3) derivative, 5, displays ferromagnetic nearest-neighbor and antiferromagnetic next-nearest-neighbor exchange interactions (J = 4.43 K and J' = -0.28 K; H = H(HDvV)+ S(1)DS(1) + S(2)DS(2)+ S(3)DS(3)). The magnetic behavior of the L(2)(Co(II))(3) derivative, 4, reveals only antiferromagnetic exchange analogous to 3 (J = -4.5, J' = -1.4; same Hamiltonian as for 3).
通过三肼基磷酰硫化物P(S)[N(Me)NH₂]₃(1)与邻羟基苯甲醛缩合反应制备了一种磷支撑的多齿配位配体P(S)[N(Me)N=CH-C₆H₄-o-OH]₃(2)。2与M(OAc)₂·xH₂O（M = Mn、Co、Ni，x = 4；M = Zn，x = 2）反应得到中性三核配合物[P(S)[N(Me)N=CH-C₆H₄-o-O]₃]₂M₃[M = Mn (3)、Co (4)、Ni (5)和Zn (6)]。已测定了化合物2 - 6的X射线晶体结构。3 - 6的结构表明三核金属组装体近乎线性。给定组装体中的两个末端金属离子具有扭曲八面体几何构型的N₃O₃配体环境，而中心金属离子也具有略微扭曲八面体几何构型的O₆配体环境。在所有配合物中，配体2通过三个亚氨基氮原子和三个酚氧原子与金属离子配位；后者作为桥连配体连接末端和中心金属离子。化合物2 - 6在固态下还显示出分子间C-H...S=P接触，这导致形成聚合物超分子结构。对于(s = 5/2)₃L₂(Mn(II))₃衍生物3观察到的磁数据显示出反铁磁最近邻和次近邻交换作用（J = -4.0 K和J' = -0.15 K；使用自旋哈密顿量H(HDvV) = -2J(S₁S₂ + S₂S₃) - 2J'S₁S₃）。相比之下，(s = 1)₃L₂(Ni(II))₃衍生物5显示出铁磁最近邻和反铁磁次近邻交换相互作用（J = 4.43 K和J' = -0.28 K；H = H(HDvV)+ S₁DS₁ + S₂DS₂+ S₃DS₃）。L₂(Co(II))₃衍生物4的磁行为仅显示出与3类似的反铁磁交换作用（J = -4.5，J' = -1.4；与3使用相同的哈密顿量）。
