一种具有长波长吸收和高光敏产率单线态氧的新型杂核钌 (II) 多吡啶配合物。

A new heteroleptic ruthenium(II) polypyridyl complex with long-wavelength absorption and high singlet-oxygen quantum yield.

机构信息

Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R. China.

出版信息

Chemistry. 2010 Mar 8;16(10):3157-65. doi: 10.1002/chem.200902563.

DOI:10.1002/chem.200902563

PMID:20108277

Abstract

Ruthenium(II) polypyridyl complexes with long-wavelength absorption and high singlet-oxygen quantum yield exhibit attractive potential in photodynamic therapy. A new heteroleptic Ru(II) polypyridyl complex, Ru(bpy)(dpb)(dppn) (bpy=2,2'-bipyridine, dpb=2,3-bis(2-pyridyl)benzoquinoxaline, dppn=4,5,9,16-tetraaza-dibenzo[a,c]naphthacene), is reported, which exhibits a (1)MLCT (MLCT: metal-to-ligand charge transfer) maximum as long as 548 nm and a singlet-oxygen quantum yield as high as 0.43. Steady/transient absorption/emission spectra indicate that the lowest-energy MLCT state localizes on the dpb ligand, whereas the high singlet-oxygen quantum yield results from the relatively long (3)MLCT(Ru-->dpb) lifetime, which in turn is the result of the equilibrium between nearly isoenergetic excited states of (3)MLCT(Ru-->dpb) and (3)pipi*(dppn). The dppn ligand also ensures a high binding affinity of the complex towards DNA. Thus, the combination of dpb and dppn gives the complex promising photodynamic activity, fully demonstrating the modularity and versatility of heteroleptic Ru(II) complexes. In contrast, Ru(bpy)(2)(dpb) shows a long-wavelength (1)MLCT maximum (551 nm) but a very low singlet-oxygen quantum yield (0.22), and Ru(bpy)(2)(dppn) shows a high singlet-oxygen quantum yield (0.79) but a very short wavelength (1)MLCT maximum (442 nm).

摘要

钌（II）多吡啶配合物具有长波长吸收和高光动力治疗中高单重态氧量子产率，具有很大的应用潜力。报道了一种新的异双核钌（II）多吡啶配合物[Ru(bpy)(dpb)(dppn)]²⁺（bpy=2,2′-联吡啶，dpb=2,3-双（2-吡啶基）苯并喹喔啉，dppn=4,5,9,16-四氮杂二苯并[a,c]萘），它具有长达 548nm 的（1）MLCT（MLCT：金属到配体的电荷转移）最大吸收峰和高达 0.43 的单线态氧量子产率。稳态/瞬态吸收/发射光谱表明，最低能量的 MLCT 态局域在 dpb 配体上，而高光动力治疗中高的单线态氧量子产率源于相对较长的（3）MLCT（Ru→dpb）寿命，这反过来又是（3）MLCT（Ru→dpb）和（3）pipi*（dppn）的几乎等能激发态之间的平衡的结果。dppn 配体也确保了该配合物与 DNA 的高结合亲和力。因此，dpb 和 dppn 的组合赋予了该配合物有前景的光动力活性，充分展示了异双核钌（II）配合物的模块化和多功能性。相比之下，[Ru(bpy)₂(dpb)]²⁺表现出长波长（1）MLCT 最大吸收峰（551nm）但非常低的单线态氧量子产率（0.22），而[Ru(bpy)₂(dppn)]²⁺表现出高光动力治疗中高的单线态氧量子产率（0.79）但非常短的波长（1）MLCT 最大吸收峰（442nm）。