Patrocínio Antonio Otávio T, Iha Neyde Y Murakami
Laboratory of Inorganic Photochemistry and Energy Conversion, Instituto de Química -Universidade de São Paulo, AV. Prof. Lineu Prestes, 748, 05508-900, São Paulo, SP, Brazil.
Inorg Chem. 2008 Dec 1;47(23):10851-7. doi: 10.1021/ic800504a.
The fac-[Re(CO)3(Me4phen)(trans-L)]+ complexes, Me4phen = 3,4,7,8-tetramethyl-1,10-phenanthroline and L = 4-styrylpyridine, stpy, or 1,2-bis(4-pyridyl)ethylene, bpe, were synthesized and characterized by their spectroscopic,photochemical, and photophysical properties. The complexes exhibit trans-to-cis isomerization upon 313, 334, 365,and 404 nm irradiation, and the true quantum yields can be efficiently determined by absorption changes combined with 1H NMR data. For fac-[Re(CO)3(Me4phen)(trans-bpe)]+ similar quantum yields were determined at all wavelengths investigated. However, a lower value (phitrue = 0.35) was determined for fac-[Re(CO)3(Me4phen)(trans-stpy)]+ at404 nm irradiation, which indicates different pathways for the photoisomerization process. The photoproducts, fac-[Re(CO)3(Me4phen)(cis-L)]+, exhibit luminescence at room temperature with two maxima ascribed to the 3ILMe4phen and 3MLCTRe-->Me4phen excited states. The luminescence properties were investigated in different media, and the behavior in glassy EPA at 77 K showed that the contribution of each emissive state is dependent on the excitation wavelength. The photochemical and photophysical behavior of the complexes were rationalized in terms of the energy gap of excited states and can be exploited in photoswitchable luminescent rigidity sensors.
合成了 fac-[Re(CO)₃(Me₄phen)(反式-L)]⁺配合物，其中 Me₄phen = 3,4,7,8-四甲基-1,10-菲咯啉，L = 4-苯乙烯基吡啶（stpy）或 1,2-双(4-吡啶基)乙烯（bpe），并通过其光谱、光化学和光物理性质对其进行了表征。这些配合物在 313、334、365 和 404 nm 光照下会发生反式到顺式的异构化，并且通过吸收变化结合¹H NMR 数据可以有效地确定真实量子产率。对于 fac-[Re(CO)₃(Me₄phen)(反式-bpe)]⁺，在所有研究的波长下都测定了相似的量子产率。然而，在 404 nm 光照下，fac-[Re(CO)₃(Me₄phen)(反式-stpy)]⁺的量子产率较低（真实量子产率 φtrue = 0.35），这表明光异构化过程存在不同的途径。光产物 fac-[Re(CO)₃(Me₄phen)(顺式-L)]⁺在室温下发光，有两个最大值，分别归因于³ILMe₄phen 和³MLCTRe→Me₄phen 激发态。在不同介质中研究了发光性质，在 77 K 的玻璃态 EPA 中的行为表明，每个发射态的贡献取决于激发波长。根据激发态的能隙对配合物的光化学和光物理行为进行了合理解释，并且这些配合物可用于光开关发光刚性传感器。
