Remarkably Intense Emission from Ruthenium(II) Complexes with Multiple Borane Centers

详细信息    查看全文

• 作者：Atsushi Nakagawa ; Eri Sakuda ; Akitaka Ito ; Noboru Kitamura
• 刊名：Inorganic Chemistry
• 出版年：2015
• 出版时间：November 2, 2015
• 年：2015
• 卷：54
• 期：21
• 页码：10287-10295
• 全文大小：509K
• ISSN：1520-510X

文摘

The electrochemical, spectroscopic, and phophysical properties of a series of Ru(II) complexes having a triarylborane-appended 2,2鈥?bipyridine (bpy) ligand(s) (RuBbpys: [Ru(Bbpy)_n(bpy)_3鈥?i>n]²⁺ (B1n) and [Ru(B₂bpy)_n(bpy)_3鈥?i>n]²⁺ (B2n), B = (dimesityl)boryldurylethynyl group(s) at the 4- or 4,4鈥?position(s) in bpy, n = 1鈥?) are described. In the excited states of the complexes, the intramolecular charge transfer transitions between the 蟺-orbital of the aryl group and the vacant p-orbital on the boron atom (蟺(aryl)鈥損(B) CT) synergistically interact with the metal-to-ligand charge transfer (MLCT) transitions. The molar absorption coefficient of the MLCT band (蔚(MLCT)) of the complex increased with increasing n, and B23 showed extremely intense absorption with 蔚(MLCT) = 5.6 脳 10⁴ M^鈥?聽cm^鈥? at 488 nm. Furthermore, B23 showed the highest emission quantum yield (0.43) among those of the polypyridine Ru(II) complexes hitherto reported. As one of the interesting results, we report that the radiative rate constant of B2n shows the correlation with 蔚(MLCT). The effects of the synergistic MLCT/蟺(aryl)鈥損(B) CT interactions on the spectroscopic and photophysical characteristics of RuBbpys are discussed in detail.