A series of zinc phthalocyanines (ZnPcs) tetra-substituted with 1,3-di[2-(2-ethoxyethoxy)ethoxy]-2-propanol (1a) or 1,3-di[2-(2-ethoxyethoxy)ethoxy]-2-propanethiol (1b) at peripheral (β) (6aâb) and non-peripheral (α) (7aâb) positions have been synthesized and characterized. The spectroscopic, photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation and photodegradation) properties of these newly synthesized phthalocyanines have been investigated in DMSO. The effects of the position of the substituents on the phthalocyanine skeleton and the nature of the linker heteroatom on their spectroscopic, photophysical and photochemical properties have been determined. The quenching behavior of the zinc phthalocyanines by 1,4-benzoquinone has been studied in DMSO. All of the zinc(II) Pc complexes (6aâb and 7aâb) showed similar electronic absorption spectra in various solvents (chloroform, dichloromethane, DMF, DMSO, THF and toluene). However, complex 7a gave an extra red-shifted band at 742 nm in chloroform and dichloromethane. DFT and TD-DFT computations were performed on the model structures (8aâd, pp-8aâd and 9aâd) to find out the cause of the extra red-shifted Q band (J-type aggregation or protonation of the Pc ring). The computational results showed that monoprotonation of a meso nitrogen atom leads to the formation of this extra band. Photophysical and photochemical measurements indicated that these newly synthesized ZnPc derivatives are promising candidates for use as photosensitizers in the application of PDT.
我们合成并表征了一系列在周边(δ)(6aâb)和非周边(δ)(7aâb)位置用 1,3-二[2-(2-乙氧基乙氧基)乙氧基]-2-
丙醇(1a)或 1,3-二[2-(2-乙氧基乙氧基)乙氧基]-2-丙
硫醇(1b)四取代的
锌酞菁(ZnPcs)。在
DMSO 中研究了这些新合成
酞菁的光谱、光物理(荧光量子产率和寿命)和光
化学(单线态氧生成和光降解)特性。确定了取代基在
酞菁骨架上的位置以及连接杂原子的性质对其光谱、光物理和光
化学性质的影响。在
二甲基亚砜中研究了 1,4-苯醌对
锌酞菁的淬灭行为。在各种溶剂(
氯仿、
二氯甲烷、
DMF、
二甲基亚砜、
四氢呋喃和
甲苯)中,所有
锌(II)
酞菁配合物(6aâb 和 7aâb)都显示出相似的电子吸收光谱。然而,在
氯仿和
二氯甲烷中,复合物 7a 在 742 纳米波长处出现了额外的红移波段。对模型结构(8aâd、pp-8aâd 和 9aâd)进行了 DFT 和 TD-DFT 计算,以找出产生额外红移 Q 波段的原因(J 型聚集或 Pc 环的质子化)。计算结果表明,介氮原子的
单质子化导致了这一额外频带的形成。光物理和光
化学测量结果表明,这些新合成的 ZnPc 衍
生物有望作为光敏剂应用于光
化学疗法。