异构的蒽乙烯单钌配合物：合成与表征、电化学、光谱性质及理论计算

Synthesis,Electrochemical and Spectral Properties,Theoretical Calculations of Isomeric Anthracene Vinyl Mononuclear Ruthenium Complexes

通过9-蒽乙炔基及2-蒽乙炔基分别与有机金属氢化物羰基氯氢三(三苯基膦)钌(Ⅱ)[Ru HCl(CO)(PPh_3)_3]反应,再使用三甲基膦(PMe_3)交换配体,合成并表征了具有同分异构结构的蒽乙烯单钌配合物1和2,其中配合物2的结构还经X射线单晶衍射的确证,结合理论计算研究了其电学及光学性质。密度泛函理论(DFT)优化配合物1和2的电子结构显示,在两个异构体中钌乙烯基与蒽配体呈现明显不同的构型,前线分子轨道图显示最高已占分子轨道(HOMO)上电子离域于整个分子骨架,其中以配体蒽乙烯基所占比例为90%,表明蒽乙烯基配体参与该配合物氧化进程的比例很大。电化学实验结果表明,配合物1的氧化还原可逆性明显低于配合物2。配合物1和2及前体分子1b和2b的电子吸收光谱结果表明,配合物与前体分子相比光谱性质呈现明显变化,其在紫外区域的强吸收峰明显减弱,而在长波长方向均出现了弱而宽的吸收峰,该吸收峰已经通过含时密度泛函理论(TDDFT)计算将其归属于π→π*以及金属配位电荷转移(MLCT)跃迁吸收,均来自于HOMO→LUMO跃迁产生。荧光发射光谱揭示金属配位之后其荧光强度和荧光量子产率明显降低。CCDC:1488284,2。

Anthracene vinyl mononuclear ruthenium isomeric complexes 1 and 2 were synthesized from 9-ethynylanthracene and 2-ethynylanthracene, carbonylchlorohydridotris （ triphenylphosphine ） ruthenium （ 11 ） [ RuHCI（CO） （ PPh3 ） 3 ] and trimethylphosphine（ PMe3 ） for ligand exchange, The structure of complex 2 was further confirmed by X-ray single crystal diffraction. Their electrical and optical properties were investigated in combination with theoretical calculations. Electronic structures of complexes 1 and 2 from density functional theory（DFT） optimization show that ruthenium vinyl and anthracene ring have different configurations in two isomers. Frontier molecular orbitals from DFT calculations feature that electron delocalized over the whole molecule in HOMO, and with larger proportion （90%） in anthracene vinyl parts. This suggests that anthracene vinyl ligand mainly participate in redox process. Electrochemical studies indicate that redox reversibility of complex 1 is lower than that of complex 2. Electronic absorption spectra of complexes 1, 2 and precursor molecules 1b, 2b exhibit obvious changes. The absorptions in UV region of complexes 1 and 2 collapse in comparison with that of molecules lb and 2b, and appear a weak and broad absorptions in long wavelength direction, which are assigned to π→π＊ and metal-to-ligand charge-transfer（MLCT） absorptions from highest occupied molecular orbital（HOMO）→lower unoccupied molecular orbital（LUMO） transitions by time-dependent DFT （TDDFT） calculation. The fluorescence emission spectrum reveals that fluorescence intensity and fluorescence quantum yields drop sharply after the ruthenium coordinate to anthracene vinyl. CCDC of complex 2 ： 1488284. Keywords anthracene vinyl; monoruthenium complex; electrochemistry ; spectrum properties; density functional theory and time-dependent density functional theory calculations