Lü Zhengliang, Yuan Mei, Pan Feng, Gao Song, Zhang Deqing, Zhu Daoben
Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China.
Inorg Chem. 2006 May 1;45(9):3538-48. doi: 10.1021/ic051648l.
Tetradentate Schiff base ligands H2L (H2saltmen, H2salen, H2-5-Brsalen, and H2-3,5-Brsalen), derived from the condensation of the corresponding salicylaldehyde or its derivatives with 1,1,2,2-tetramethylethyldiamine or 1, 2-diaminoethane, reacted with Mn(III) acetate or perchlorate salts and sodium azide or sodium cyanate to produce five Mn(III) dimer complexes, [Mn(saltmen)(O2CCH3)]2.2CH3CO2H (1), [Mn(saltmen)(N3)]2 (2), [Mn(salen)(NCO)]2 (3), [Mn(3,5-Brsalen)(3,5-Brsalicylaldehyde)]2 (4), and [Mn(5-Brsalen)(CH3OH)]2(ClO4)2 (5). These new complexes have been characterized by IR, elemental analyses, crystal structural analyses, and magnetic studies. Within these Mn(III) dimeric complexes, two Mn(III) ions are connected by phenolate oxygen atoms with acetate, azide, cyanate, a 3,5-Brsalicyladehyde anion, and a neutral methanol molecule as the axial ligands for complexes 1-5, respectively. Complexes 1-4 exhibit intradimer ferromagnetic exchange and display frequency dependence of ac magnetic susceptibility, possibly showing single-molecule-magnet (SMM) behavior. In contrast, complex 5 shows an intradimer antiferromagnetic coupling probably originating from the relatively shorter Mn-O distance, compared to those of complexes 1-4.
四齿席夫碱配体H2L（H2saltmen、H2salen、H2 - 5 - Brsalen和H2 - 3,5 - Brsalen），由相应的水杨醛或其衍生物与1,1,2,2 - 四甲基乙二胺或1,2 - 二氨基乙烷缩合而成，与醋酸锰（III）或高氯酸盐以及叠氮化钠或氰酸钠反应，生成了五种Mn（III）二聚体配合物，[Mn（saltmen）（O2CCH3）]2·2CH3CO2H（1）、[Mn（saltmen）（N3）]2（2）、[Mn（salen）（NCO）]2（3）、[Mn（3,5 - Brsalen）（3,5 - 溴水杨醛）]2（4）和[Mn（5 - Brsalen）（CH3OH）]2（ClO4）2（5）。这些新配合物通过红外光谱、元素分析、晶体结构分析和磁性研究进行了表征。在这些Mn（III）二聚体配合物中，两个Mn（III）离子分别通过酚氧原子与醋酸根、叠氮根、氰酸根、3,5 - 溴水杨醛阴离子和中性甲醇分子相连，作为配合物1 - 5的轴向配体。配合物1 - 4表现出二聚体内铁磁交换，并显示出交流磁化率的频率依赖性，可能表现出单分子磁体（SMM）行为。相比之下，配合物5表现出二聚体内反铁磁耦合，这可能源于与配合物1 - 4相比相对较短的Mn - O距离。
