Studies on Magneto-Photo Multifunctional System of Polynuclear Complexes Comprised by Discrete Metal Complexes

通过水杨醛同质物与4,6-二氨基间苯二酚的反应，合成了两个分离配位的新型多齿配体H_4L4-X和H_3L5-X（X=H,CH_3,Br）。制备了新的三核锰（III）配合物[Mn(L5-X)(CH_3OH)]_3 (X=-H;1,-CH_3;2, -Br;3)，并用X射线结构分析对其进行了表征。1的三核结构如图1所示。三个锰（III）中心被（L5-H）^<3->隔开，Mn…Mn的距离在8.07(3)-8.18(1)Å之间。各锰离子沿O_<溶剂>-Mn-N_<恶唑啉>轴呈细长八面体构型。1的CPK模型如图2所示。分子结构被认为是一个带腔的大三角金字塔。空腔的直径估计为3 Å，配合物可能将小分子纳入空腔。由于NH_4^+具有亲水氧和C_3对称性，因此可以很好地调节空腔。配合物1与NH_4PF_6在氯仿中反应生成红棕色微晶体。所得化合物的红外光谱分别在3212和847 cm^<-1>处显示出强烈的N-H和P-F振动。DMF测定产物的摩尔电导率为96 μ m^2mor^<-1>。结果表明，所得化合物的分子式为[Mn_3(L5-H)_3(CH_3OH)_3(NH_4)]_3PF_6（1’）。1′中的铵离子被引入到三核配合物单元的空腔中。

The new polydentate ligands, H_4L4-X and H_3L5-X(X=H,CH_3,Br), combined two separative coordination sites have been synthesized by reaction of salicylaldehyde homologues and 4,6-diamino-resorcinol. The new trinuclear manganese(III) complexes, [Mn(L5-X)(CH_3OH)]_3 (X=-H;1,-CH_3;2,and -Br;3) have been prepared and characterized by X-ray structure analysis. The trinuclear structure of 1 is shown in Figure 1.Three manganese(III) centers are separated by (L5-H)^<3->, and the Mn...Mn distances lie in the range 8.07(3)-8.18(1) Å. Each manganese ion adopts an elongated octahedral configuration along with O_<solvent>-Mn-N_<oxazoline> axis. The CPK models for 1 are shown in Figure 2.The molecular structure is regarded as a large trigonal pyramid with cavity. Extent of the cavity is estimated as 3 Å in diameter, and the complexes potentially can incorporate small molecules into the cavity. It is expected that the cavity is well adjustable for NH_4^+ because it has hydrophilic oxygens and C_3 symmetry. The reaction of complex 1 and NH_4PF_6 in chloroform gave reddish brown microcrystals. The IR spectrum of the obtained compound showed strong N-H and P-F vibrations at 3212 and 847 cm^<-1>, respectively. Molar conductivity of the products determined in DMF was 96 Scm^2mor^<-1>. The results suggest that the obtained compound formulated as [Mn_3(L5-H)_3(CH_3OH)_3(NH_4)]_3PF_6 (1'). The ammonium ion in 1' was incorporated into the cavity of trinuclear complex unit.