Effect of methylene spacers on the spectral, electrochemical, and structural properties of bis(4,4′-disubstituted-2,2′-bipyridyl) ruthenium(ii) dye analogues
作者:Sheri Lense、Kenneth I. Hardcastle、Cora E. MacBeth
DOI:10.1039/b905551g
日期:——
Two new ruthenium complexes, [Ru(L1OMe)2(NCS)2] and [Ru(L2OMe)2(NCS)2] (where L1OMe = 2,2â²-bipyridine-4,4â²-di(methyl ethanoate) and L2OMe = 2,2â²-bipyridine-4,4â²-di(methyl propionate)), have been synthesized and characterized using spectroscopic and electrochemical techniques. The [Ru(L2OMe)2(NCS)2] complex has also been characterized by X-ray diffraction studies and reveals a distorted octahedral coordination geometry about the ruthenium center. Cyclic voltammetry studies of both complexes exhibit quasi-reversible Ru(II/III) couples and a number of ligand reduction events. The complex with one methylene spacer between the bipyridyl ligand and the methyl ester functional group, [Ru(L1OMe)2(NCS)2], was particularly unstable under reducing conditions. The properties of these complexes are compared with the ethyl ester analogue of the N3 photosensitizer [Ru(L0OEt)2(NCS)2].
我们利用光谱和电化学技术合成了[Ru(L1OMe)2(NCS)2]和[Ru(L2OMe)2(NCS)2](其中 L1OMe = 2,2â²-联吡啶-4,4â²-二(甲基乙酸酯)和 L2OMe = 2,2â²-联吡啶-4,4â²-二(甲基丙酸酯))这两种新的钌配合物。钌(L2OMe)2(NCS)2] 复合物也通过 X 射线衍射研究进行了表征,并揭示了钌中心的畸变八面体配位几何。对这两种配合物的循环伏安研究显示出准可逆的 Ru(II/III)偶联和一些配体还原事件。在双吡啶配体和甲酯官能团之间有一个亚甲基间隔的[Ru(L1OMe)2(NCS)2]配合物在还原条件下尤其不稳定。我们将这些配合物的性质与 N3 光敏剂[Ru(L0OEt)2(NCS)2]的乙酯类似物进行了比较。