异质金属竞争配位用于混合配体型氯代异烟酸铀酰配合物的合成调控北大核心CSCD

本工作从基于2,6-二氯异烟酸(H-2,6-dcpca)和2,2′-联吡啶(2,2′-bpy)混合配体的卤代异烟酸铀酰配合物((UO;)(2,6-dcpca);(2,2′-bpy))出发,通过进一步引入第二金属中心(Ag;、Zn;和Cu;)进行竞争配位,实现了对这一混合配体型氯代异烟酸铀酰配合物的结构调控,并成功合成了六种新型混合配体型异质金属铀酰配合物。单晶结构分析表明,这些异质金属节点具有不同的配位行为,可以参与2,2′-bpy和[2,6-dcpca];配体的竞争配位并改变铀酰中心的配位环境,导致最终形成的水热产物具有不同铀酰配位模式和化学结构。同时,由于晶体结构的不同,这些化合物在超分子晶格中的弱相互作用和晶格堆积方式也表现出较大变化。通过第二金属中心的竞争配位策略,实现了混合配体型铀酰配合物中铀酰配位模式的调控及多种异质金属铀酰化合物的制备,证明了基于多重竞争配位的合成调控策略的可行性,并有望在未来用于更多的功能性锕系-有机杂化材料的合成。

Competitive Coordination of Heterometallic Ions for Synthetic Regulation of Mixed-Ligand Uranyl Coordination Compounds of Halogen-Substituted Isonicotinate

In this work, second metal centers are introduced to regulate the coordination behavior of uranyl center in mixed-ligand uranyl compounds with halogen-substituted dichloroisonicotinic acid(H-2, 6-dcpca) and 2, 2′-bipyridine(2, 2′-bpy). Through a strategy of diversified competitive coordination via a second metal center(Ag⁺, Zn²⁺ and Cu²⁺), the coordination environment of mixed-ligand uranyl complex was tuned, and six heterometallic uranyl compounds with different second ions, Ag⁺, Zn²⁺ or Cu²⁺, were successfully acquired by hydrothermal synthesis. Single-crystal structures show that these heterometallic nodes can coordinate with ［2, 6-dcpca］- and 2, 2′-bpy as the competitive candidate of uranyl center, and finally lead to different hydrothermal products with varying uranyl coordination patterns and molecular structures. Due to the difference in molecular structure, weak interactions and stacking modes in the supramolecular lattice of these compounds also show different changes. The regulation strategy based on diversified competitive coordination as well as the mixed-ligand method proposed here have been proved to be feasible to achieve the preparation of a diversity of heterometallic uranyl compounds and can be expected to be used for the synthesis and preparation of more valuable functional actinide-organic hybrid materials.