Ramos Luiz Duarte, da Cruz Hugo Moreira, Morelli Frin Karina P
Universidade Federal do ABC - UFABC, Av. dos Estados 5001, Santo Andre, SP, Brazil09210-170.
Photochem Photobiol Sci. 2017 Apr 12;16(4):459-466. doi: 10.1039/c6pp00364h.
fac-[Re(ampy)(CO)(NN)] complexes (ampy = 2-aminomethylpyridine and NN = 1,10-phenanthroline (phen), and 2,2'-bipyridine (bpy)) were synthesized, purified and characterized by proton nuclear magnetic resonance (H NMR), UV-visible and Fourier-transformed infrared (FT-IR) spectroscopies, and their photophysical properties were investigated using steady state and time-resolved emission spectroscopies. The electronic absorption spectra exhibit two main absorption bands: the higher energy band, which was assigned to intraligand transition (IL), and the lower energy band assigned to metal-to-ligand charge transfer (MLCT). Both complexes showed emission at room temperature in a CHCN solution (λ = 560 nm, ϕ = 0.091, τ = 560 ns for fac-[Re(ampy)(CO)(phen)]; λ = 568 nm, ϕ = 0.024, τ = 100 ns for fac-[Re(ampy)(CO)(bpy)]) and rigid media (λ = 530 nm, τ = 3300 ns for fac-[Re(ampy)(CO)(phen)]; λ = 530 nm, τ = 853 ns for fac-[Re(ampy)(CO)(bpy)]) arising from the lowest lying MLCT excited state. Both complexes along with fac-[Re(L)(CO)(NN)] complexes, L = Cl or pyridine, were capable of efficiently photosensitizing the generation of singlet oxygen with quantum yield in the range of 0.59-0.28. These results highlight the potential application of fac-[Re(L)(CO)(NN)] complexes in the development of sensitizers for the generation of singlet oxygen.
合成了 fac-[Re(ampy)(CO)(NN)] 配合物（ampy = 2-氨甲基吡啶，NN = 1,10-菲咯啉（phen）和 2,2'-联吡啶（bpy）），通过质子核磁共振（H NMR）、紫外可见光谱和傅里叶变换红外（FT-IR）光谱对其进行了纯化和表征，并使用稳态和时间分辨发射光谱研究了它们的光物理性质。电子吸收光谱显示出两个主要吸收带：较高能量的带，归属于配体内跃迁（IL）；较低能量的带，归属于金属到配体的电荷转移（MLCT）。两种配合物在 CHCN 溶液中室温下均有发射（对于 fac-[Re(ampy)(CO)(phen)]，λ = 560 nm，ϕ = 0.091，τ = 560 ns；对于 fac-[Re(ampy)(CO)(bpy)]，λ = 568 nm，ϕ = 0.024，τ = 100 ns），在刚性介质中也有发射（对于 fac-[Re(ampy)(CO)(phen)]，λ = 530 nm，τ = 3300 ns；对于 fac-[Re(ampy)(CO)(bpy)]，λ = 530 nm，τ = 853 ns），这是由最低的 MLCT 激发态引起的。这两种配合物与 fac-[Re(L)(CO)(NN)] 配合物（L = Cl 或吡啶）都能够有效地光敏化单线态氧的产生，量子产率在 0.59 - 0.28 范围内。这些结果突出了 fac-[Re(L)(CO)(NN)] 配合物在开发单线态氧产生敏化剂方面的潜在应用。
