灵活 bis ((β-diketonato) 连接体的协调复合体中的相依赖的聚合异构体
Manuel Imperato1,2, Alessio Nicolini1, Matteo Boniburini1
1Dipartimento di Scienze Chimiche e Geologiche e UdR INSTM, Università degli Studi di Modena e Reggio Emilia, via G. Campi 103, 41125 Modena, Italy. acornia@unimore.it.
Dalton transactions (Cambridge, England : 2003)
|November 4, 2024
概括
这项研究详细介绍了一种 (II) 复合物[Co2 (bdhb) 2 (py) 4],该复合物表现出缓慢的磁放松. 在溶液中,这个二维复合物重新排列成单体物种,在金属有机化合物中证明了聚合异构.
科学领域:
- 协调化学 协调化学
- 磁电化学 磁电化学 磁电化学
- 超分子化学 超分子化学
背景情况:
- 亲联体1,3-bis(3,5-dioxo-1-hexyl) (H2bdhb) 存在于有机溶液中的复合体混合物中.
- 含有H2bdhb的二度 ((II) 复合物可以表现出有趣的磁性特性.
- 聚合异构是一种在金属有机添加物中观察到的现象.
研究的目的:
- 合成和表征一个二面性 ((II) 复合物与H2bdhb和pyridine.
- 为了研究二维复合体的磁性,包括磁性放松.
- 研究复合物在有机溶剂中的溶液行为和结构变化.
主要方法:
- 合成二面性 (II) 复合物[Co2 (bdhb) 2 (py) 4].
- 磁性测量,X波段EPR光谱学,以及CASSCF/NEVPT2计算.
- 质谱学,UV-Vis,1H/2H NMR和DOSY用于溶液的表征.
- DFT和CASSCF/NEVPT2计算以结构分析的元动力学模拟为指导.
主要成果:
- 晶体二极体复合体[Co2 ((bdhb) 2 ((py) 4)) 具有两个非相互作用的高旋转 ((II)) 离子,具有显著的轻平面异构性.
- 在冷温度下观察到缓慢的磁放松,归因于直接和拉曼机制.
- 在溶液中,二元复合物重新排列为单体物种,具有部分连接体解离和改变的协调环境.
结论:
- 二维 (II) 复合体呈现缓慢的磁放松,并在溶液中经历聚合异构.
- 该研究提供了聚合异构的第二个例子,即bdhb2-与双价金属离子的1:1 adducts.
- 计算方法准确地重现了实验对固态和溶液结构的观察结果.
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