Structures and ligand exchange of N-confused porphyrin dimer complexes with group 12 metals
Structures and ligand exchange of N-confused porphyrin dimer complexes with group 12 metals
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DOI：
10.1021/ic035294e
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发表时间：
2004-03-08
影响因子：
4.6
通讯作者：
Osuka, A
中科院分区：
文献类型：
--
作者：
Furuta, H;Morimoto, T;Osuka, A
N-混乱的5，20-二苯基卟啉（NCDPP，1）与第12族金属在固态和溶液中都能形成2：2的二聚体配合物。Zn（II）和Cd（II）配合物的X射线单晶分析（7，8）表明，每个金属离子与三个内核氮和一个外围氮的另一个NCDPP对协调。在7、8和Hg（II）络合物（9）的H-1 NMR光谱中，由于配位卟啉的环电流效应，混乱吡咯环的外部α-H信号分别出现在2.57、3.44和3.60 ppm的高场区域。在Cd（II）和Hg（II）配合物（8，9）的情况下，观察到与配偶体环的金属核的额外的磁耦合。在25 degreesC的单体交换反应的平衡常数（K）被确定为2.5，1.3，和0.6分别为（Zn-Cd），（Cd-Hg），和（Zn-Hg）异二聚体络合物，从H-1 NMR光谱的溶液中含有两种不同的二聚体。此外，从Zn（II）NCP二聚体配合物的游离碱卟啉的金属转移反应被证明。
N-confused 5,20-diphenylporphyrin (NCDPP, 1) formed 2:2 dimer complexes with group 12 metals both in the solid state and in solution. X-ray single-crystal analyses of the Zn(II) and Cd(II) complexes (7, 8) revealed that each metal ion is coordinated with three inner core nitrogens and a peripheral nitrogen of the other NCDPP in the pair. In the H-1 NMR spectra of 7, 8, and the Hg(II) complex (9), the outer alpha-H signals of the confused pyrrole ring appeared in the upfield region at 2.57, 3.44, and 3.60 ppm, respectively, due to the ring current effect by the coordinated porphyrins. In the case of the Cd(II) and Hg(II) complexes (8, 9), additional magnetic couplings with the metal nuclei of the partner rings were observed. The equilibrium constants (K) of the monomer exchange reaction at 25 degreesC were determined to be 2.5, 1.3, and 0.6 for the (Zn-Cd), (Cd-Hg), and (Zn-Hg) heterodimer complexes, respectively, from the H-1 NMR spectra of a solution containing two different dimers. Furthermore, a metal-transfer reaction from a Zn(II) NCP dimer complex to the free base porphyrin was demonstrated.