Fotopoulou Evangelia-Spyridoula, Panagiotou Nikos, Tasiopoulos Anastasios J, Turnbull Mark M, Perlepes Spyros P, Nastopoulos Vassilios
University of Patras, Department of Chemistry, 26504 Patras, Greece.
University of Cyprus, Department of Chemistry, 1678 Nicosia, Cyprus.
Dalton Trans. 2025 Sep 23;54(37):14013-14024. doi: 10.1039/d5dt01389e.
With the aim of assessing the role and impact of pseudohalides on the molecular and supramolecular structures of copper(II)/heavily substituted imidazole complexes, the synthesis and characterization of the complexes {[Cu(N)(HL)]} (1), {[Cu{N(CN)}(HL)]·MeCO} (2·MeCO) and [Cu(NCO)(HL)]·MeCN (3·MeCN) have been carried out; HL is the 4,5-diphenylimidazole ligand. The organic molecule behaves as a monodentate ligand through the pyridine-type nitrogen atom of the imidazole ring. The 1D polymer 1 is made up of undulating {-Cu-(N)-Cu-(N)-} chains, with the HL ligands extending from both sides of the chains. The square pyramidal metal ions are alternately doubly bridged by two different types (basal-basal and basal-apical) of end-on azido groups. In 2·MeCO, the N(CN) ions behave as end-to-end (μ-1,5 or 2.101) ligands forming a 2D polymeric lattice, consisting of four-membered Cu rings interconnected by four dicyanamido bridges; the five-coordinate Cu ion adopts a geometry intermediate between square pyramidal and trigonal bipyramidal. The metal centre in the mononuclear complex 3·MeCN is bonded to two HL ligands and two terminal isocyanato groups; the coordination geometry of Cu is closest to a seesaw conformation. The crystal structures of the complexes are built with a variety of supramolecular interactions, including the synthons N-H⋯X (X = N and O), which are critically discussed. The IR spectra of the compounds are discussed in terms of the coordination modes of the pseudohalido ligands. The magnetic properties of 1 and 2 have also been studied in the temperature and field ranges of 1.8-300 K and 0-50 kOe, respectively. Complex 1 exhibits both ferromagnetic and antiferromagnetic Cu⋯Cu exchange interactions propagated through the two different end-on bi-azido bridges, whereas the exchange interactions are negligible (if any) in the 2D polymer 2 as a consequence of the μ-1,5 ligation mode of the dicyanamido ligand and the resultant long Cu⋯Cu distances.
为了评估拟卤化物对铜（II）/高度取代咪唑配合物的分子和超分子结构的作用及影响，我们开展了配合物{[Cu(N)(HL)]}（1）、{[Cu{N(CN)}(HL)]·MeCO}（2·MeCO）和[Cu(NCO)(HL)]·MeCN（3·MeCN）的合成与表征；HL为4,5 - 二苯基咪唑配体。有机分子通过咪唑环的吡啶型氮原子作为单齿配体。一维聚合物1由起伏的{-Cu-(N)-Cu-(N)-}链组成，HL配体从链的两侧延伸。方形金字塔形金属离子被两种不同类型（底面 - 底面和底面 - 顶面）的端基叠氮基团交替双桥连。在2·MeCO中，N(CN)离子作为端对端（μ - 1,5或2.101）配体形成二维聚合物晶格，由通过四个二氰胺桥相互连接的四元铜环组成；五配位铜离子采用介于方形金字塔形和三角双锥形之间的几何构型。单核配合物3·MeCN中的金属中心与两个HL配体和两个末端异氰酸酯基团相连；铜的配位几何构型最接近跷跷板构象。配合物的晶体结构由多种超分子相互作用构建而成，包括合成子N - H⋯X（X = N和O），对此进行了深入讨论。根据拟卤化物配体的配位模式讨论了化合物的红外光谱。还分别在1.8 - 300 K和0 - 50 kOe的温度和磁场范围内研究了1和2的磁性。配合物1表现出通过两种不同的端基双叠氮桥传播的铁磁和反铁磁Cu⋯Cu交换相互作用，而由于二氰胺配体的μ - 1,5配位模式以及由此产生的长Cu⋯Cu距离，二维聚合物2中的交换相互作用可忽略不计（如果有的话）。
