Theoretical studies on Ru(fppz)2(CO)L (L = N -heterocyclic ligand): Electronic structure, absorption, phosphorescence, and solvatochromism

A series of ruthenium(II) complexes Ru(fppz)₂(CO)L [fppz = 3-trifluoromethyl-5(2-pyridyl)pyrazole; L = pyridine (1), 4-dimethylaminopyridine (2), 4-cyanopyridine (3)] were designed and investigated theoretically to explore their electronic structures, absorption, and emissions as well as the solvatochromism. The singlet ground state and triplet excited state geometries were fully optimized at the B3LYP/LANL2DZ and CIS/LANL2DZ level, respectively. The HOMO of 1–3 is composed of d_yz(Ru) atom and π(fppz). The LUMO of 1 and 2 is dominantly contributed by π*(fppz) orbital, but that of 3 is contribute by π*(L). Absorption and phosphorescence in vacuo, C₆H₁₂, and CH₃CN media were calculated using the TD-DFT level of theory with the PCM model based on the optimized ground and excited state geometries, respectively. The lowest-lying absorption of 1 and 2 at 387 and 391 nm is attributed to {[d_yz(Ru) + π(fppz)] → [π*(fppz)]} transition, but that of 3 at 479 nm is assigned to {[d_yz(Ru) + π(fppz)] → [π*(L)]} transition. The phosphorescence of 1 and 2 at 436 and 438 nm originates from ³{[d_yz(Ru) + π(fppz)] [π*(fppz)]} excited state, while that of 3 at 606 nm is from ³{[d_yz(Ru) + π(fppz)] [π*(L)]} excited state. The calculation results showed that the absorption and emission transition character can be changed from MLCT/ILCT to MLCT/LLCT transition by altering the substituent on the L ligand. The phosphorescence of 1 and 2 does not have solvatochromism, but that of 3 at 606 nm (vacuo), 584 nm (C₆H₁₂), and 541 nm (CH₃CN) is strongly dependent on the solvent polarity, so introducing electron-withdrawing group on ligand L will induce remarkable solvatochromism. Supported by the National Natural Science Foundation of China (Grant Nos. 20573042, 20703015, and 20333050)     

Theoretical studies on Ru(fppz)2(CO)L (L = N-heterocyclic ligand): Electronic structure, absorption, phosphorescence, and solvatochromism

A series of ruthenium(II) complexes Ru(fppz)₂(CO)L [fppz = 3-trifluoromethyl-5(2-pyridyl)pyrazole; L = pyridine (1), 4-dimethylaminopyridine (2), 4-cyanopyridine (3)] were designed and investigated theoretically to explore their electronic structures, absorption, and emissions as well as the solvatochromism. The singlet ground state and triplet excited state geometries were fully optimized at the B3LYP/LANL2DZ and CIS/LANL2DZ level, respectively. The HOMO of 1–3 is composed of d_yz(Ru) atom and π(fppz). The LUMO of 1 and 2 is dominantly contributed by π*(fppz) orbital, but that of 3 is contribute by π*(L). Absorption and phosphorescence in vacuo, C₆H₁₂, and CH₃CN media were calculated using the TD-DFT level of theory with the PCM model based on the optimized ground and excited state geometries, respectively. The lowest-lying absorption of 1 and 2 at 387 and 391 nm is attributed to {[d_yz(Ru) + π(fppz)] → [π*(fppz)]} transition, but that of 3 at 479 nm is assigned to {[d_yz(Ru) + π(fppz)] → [π*(L)]} transition. The phosphorescence of 1 and 2 at 436 and 438 nm originates from ³{[d_yz(Ru) + π(fppz)] [π*(fppz)]} excited state, while that of 3 at 606 nm is from ³{[d_yz(Ru) + π(fppz)] [π*(L)]} excited state. The calculation results showed that the absorption and emission transition character can be changed from MLCT/ILCT to MLCT/LLCT transition by altering the substituent on the L ligand. The phosphorescence of 1 and 2 does not have solvatochromism, but that of 3 at 606 nm (vacuo), 584 nm (C₆H₁₂), and 541 nm (CH₃CN) is strongly dependent on the solvent polarity, so introducing electron-withdrawing group on ligand L will induce remarkable solvatochromism.     

Interplay between intra- and interligand charge transfer with variation of the axial N-heterocyclic ligand in osmium(II) pyridylpyrazolate complexes: extensive color tuning by phosphorescent solvatochromism

The rational design and syntheses of a new series of Os(II) complexes with formula [Os(fppz)(2)(CO)(L)] (1: L=4-dimethylaminopyridine; 2: L = pyridine; 3: L = 4,4'-bipyridine; 4: L = pyridazine; 5: L = 4-cyanopyridine), bearing two (2-pyridyl)pyrazolate ligands (fppz) together with one carbonyl and one N-heterocyclic ligand at the axial positions are reported. Single-crystal X-ray diffraction studies of, for example, 2 reveal a distorted octahedral geometry in which both fppz ligands reside in the equatorial plane with a trans configuration and adopt a bent arrangement at the metal center with a dihedral angle of approximately 23 degrees , while the carbonyl and pyridine ligands are located at the axial positions. Variation of the axial N-heterocyclic ligand leads to remarkable changes in the photophysical properties as the energy gap and hence the phosphorescence peak wavelength can be tuned. For complexes 1 and 2 the solvent-polarity-independent phosphorescence originates from a combination of intraligand (3)pi-pi* ((3)ILCT) and metal-to-ligand charge transfer transitions ((3)MLCT). In sharp contrast, as supported by cyclic voltammetry measurements and theoretical calculations, complexes 3--5 exhibit mainly ligand-to-ligand charge transfer (LLCT) transitions, resulting in a large dipolar change. The phosphorescence of complexes 3--5 thus exhibits a strong dependence on the polarity of the solvent, being shifted for example, from 560 (in C(6)H(12)) to 665 nm (in CH(3)CN) and from 603 (in C(6)H(12)) to 710 nm (in CH(3)CN) for complexes 3 and 5, respectively. The results clearly demonstrate that a simple, straightforward derivatization of the axial N-heterocyclic ligand drastically alters the excitation properties per se from intraligand charge transfer (ILCT) to LLCT transitions. The latter exhibit remarkable LLCT phosphorescence solvatochromism so that a broad range of color tunability can be achieved.     

双膦钌配合物Ru（OAc）_2（Ph_3P）（dppm）和Ru（OAc）_2（

合成了双膦醋酸钌配合物，不同温度的￣１ＨＮＭＲ谱表明，两个醋酸根分别以单齿和双齿配体与中心钌（Ⅱ）配位；￣（３１）ＰＮＭＲ和Ｘ－射线结构分析表明膦配体为面式构型。配合物对丙烯酸和苯乙烯有选择氢化活性。     

[Ru(bpy)2L]2+、[Ru(phen)2L]2+(L=pytp,pztp)电子结构与抗癌活性研究

Theoretical studies on the complexes Ru(bpy)2L2+, Ru(phen)2L2+ (L=pytp,pztp) were carried out by using the density functional theory (DFT) method at B3LYP/LanL2DZ level. The relation between electronic structures and anti-cancer activities of complexes was investigated. The increasing of N in the main ligand can strengthen the interaction of complexes with DNA and anti cancer activities of complexes. The calculation results show that for complexes I-IV, their energies of LUMO orbital are in the order of εI>εII, εIII>εIV, the electron cloud components of LUMO come mainly from main ligands and the content distributing is in the order of I相似文献   

配合物[M（CO）3（PPh2py）2]（M=Fe，Ru）异构体的理论研究

对PPh2py配合物[M(CO)3(PPh2py)2](M=Fe,Ru)的三种构型的异构体1-6进行了研究.其中PPh2py以两个P原子与M配位形成HH构型1(Fe)和4(Ru),以一个P和一个N原子与M配位形成HT构型2(Fe)和5(Ru),以两个N原子与M配位形成HH'构型3(Fe)和6(Ru).结果表明,(1)PPh2py中P原子对HOMO轨道的贡献最大,PPh2py作为电子给体时易以P原子与金属原子结合.(2)从分子能量和相互作用能数据表明,配合物中HH构型最稳定,HH'构型最不稳定,这与合成产物为HH构型的结果一致.(3)键长和Wiberg键级均表明P-M键比N-M键结合力强.P、M原子间存在σ键,而N、Fe原子间仅存在nN→nM或nN→σM-P的电荷转移作用.(4)HH构型中M对HOMO的贡献最大,PPh2py向M的电荷转移最强,使M的负电荷最大,故HH构型最易作为电子给体以M原子与第二个金属配位形成双核配合物.     

三态不饱和三核钌羰基化合物的理论研究

采用两种密度泛函方法和两种有效核势基组对中性不饱和三核钌羰基化合物Ru3(CO)n(n=11,10,9)的三态异构体进行理论计算,优化出8个稳定异构体.研究发现,三态异构体中带有多个非端羰基的异构体能量较低.对同一分子的三态异构体,所含非端羰基数目越多,则能量也越低.     

1,3-二(2,6-二甲基苯基)-2-四氢咪唑基-苯亚甲基-二吡啶基-二氯合钌 化合物的合成

设计了由1,3-二(2,6-二甲基苯基)-2-四氢咪唑基-苯亚甲基-三苯基膦-二氯合钌(7)和吡啶反应生成无膦型金属钌卡宾化合物1,3-二(2,6-二甲苯基)-2-四氢咪唑基-苯亚甲基-2-吡啶基-二氯合钌(8), 8作为高效催化剂用于丙烯腈和烯丙基苯的交叉交互置换反应. 新化合物7, 8经核磁共振氢谱、碳谱和高分辨率质谱予以证实.     

Crystal Structure of[Ru(taab)(DMF)_2]·[(CIO_4)_2]

ＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆ［Ｒｕ（ｔａａｂ）（ＤＭＦ）_２］·［（ＣＩＯ_４）_２］￥ＤｕａｎＣｈｕｎ－Ｙｉｎｇ；ＬｕＺｈｏｎｇ－Ｌｉｎ；ＴｉａｎＹｕ－Ｐｅｎｇ；ＹｏｕＸｉａｏ－Ｚｅｎｇ；ＣｈｅｎＹａｏ（ＣｏｏｒｄｉｎａｔｉｏｎＣｈｅｍｉｓｔ?..     

Crystallographic report: A synthetic precursor for hetero‐binuclear metal complexes, [Ru(bpy)(dppy)2(CO)2](PF6)2 (bpy = 2,2′‐bipyridine,dppy = 2‐(diphenylphosphino)pyridine)

In the title complex, [Ru(bpy)(dppy)₂(CO)₂](PF₆)₂ (bpy = 2,2′‐bipyridine, dppy = 2‐(diphenylphosphino)pyridine), the ruthenium atom exhibits a slightly distorted octahedral coordination with the carbonyl ligands in cis positions. In addition, two dppy ligands coordinate to the ruthenium center through the phosphorus atoms in mutually trans positions and two pyridyl nitrogen atoms of the dppy direct toward two carbonyl ligands. Copyright © 2004 John Wiley & Sons, Ltd.     

DFT/TD‐DFT investigation on Ir(III) complexes with N‐heterocyclic carbene ligands: Geometries,electronic structures,absorption, and phosphorescence properties

Iridium(III) complexes with N‐heterocyclic (NHC) ligands including fac‐Ir(pmb)₃ (1), mer‐Ir(pmb)₃ (2), (pmb)₂Ir(acac) (3), mer‐Ir(pypi)₃ (4), and fac‐Ir(pypi)₃ (5) [pmb = 1‐phenyl‐3H‐benzimidazolin‐2‐ylidene, acac = acetoylacetonate, pypi = 1‐phenyl‐5H‐benzimidazolin‐2‐ylidene; fac = facial, mer = meridional] were investigated theoretically. The geometry structures of 1–5 in the ground and excited state were optimized with restricted and unrestricted DFT (density functional theory) methods, respectively (LANL2DZ for Ir atom and 6‐31G for other atoms). The HOMOs (highest occupied molecular orbitals) of 1–3 are composed of d(Ir) and π(phenyl), while those of 4 and 5 are contributed by d(Ir) and π(carbene). The LUMOs (lowest unoccupied molecular orbitals) of 1, 2, 4, and 5 are localized on carbene, but that of 3 is localized on acac. The calculated lowest‐lying absorptions with TD‐DFT method based on Perdew‐Burke‐Erzenrhof (PBE) functional of 1 (310 nm), 2 (332 nm), and 3 (347 nm) have ML_carbeneCT/IL_{phenyl→carbene}CT (MLCT = metal‐to‐ligand charge transfer; ILCT = intraligand charge transfer) transition characters, whereas those of 4 (385 nm) and 5 (389 nm) are assigned to ML_carbeneCT/IL_{carbene→carbene}CT transitions. The phosphorescences calculated by TD‐DFT method with PBE0 functional of 1 (386 nm) and 2 (388 nm) originate from ³ML_carbeneCT/³IL_{phenyl→carbene}CT excited states, but those of 4 (575 nm) and 5 (578 nm) come from ³ML_carbeneCT/³IL_{carbene→carbene}CT excited states. The calculated results showed that the carbene and phenyl groups act as two independent chromophores in transition processes. Compared with 1 and 2, the absorptions of 4 and 5 are red‐shifted by increasing the effective π‐conjugation groups near the C_carbene atom. We predicated that (pmb)₂Ir(acac) is nonemissive, because the LUMO of 3 is contributed by the nonemissive acac ligand. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010     

A new end-on azido-bridged dicopper(II) complex; syntheses,structure, solvatochromism,magnetic properties,and DFT study

Abstract

A new asymmetric azido-bridged dinuclear copper(II) complex with formula [L(N₃)Cu(μ_N,N-N₃)]₂, L = N,N-dimethyl-N′-benzyl-ethylenediamine, has been synthesized and characterized structurally and magnetically. Single-crystal structural analysis reveals the Cu(II) ions are linked by two end-on azido nitrogen atoms. The copper(II) ions adopt s penta-coordinated geometry that is intermediate between square pyramidal and trigonal bipyramidal (τ = 0.528). Variable temperature magnetic susceptibility data were collected and fitted to the appropriate equations derived from the Hamiltonian H = ?JS₁S₂ that show antiferromagnetic intradimer interactions with J = ?1.0 cm^?1 through the end-on azido bridges between the metal centers. To rationalize the magnetic behavior, a DFT calculation has been performed within the broken symmetry framework. The analyses of the magnetic orbital interaction and spin distribution indicate the nature of the magnetic properties of the complex. The complex is solvatochromic and its solvatochromism was investigated by visible spectroscopy. To explore the mechanism of interaction between the solvent molecules and the complex, different solvent parameters were utilized and analyzed by a statistical method using the multiple linear regression (MLR) method. It was found that the hydrogen bond donation (β) and polarity/polarizability (π*) parameters of the solvents lead to the solvatochromism property.     

联吡啶钌配合物[Ru(Htcterpy)X3]3-[X=NCS,CN,Cl]的电子结构和光谱性质的理论研究

利用DFT中的B3LYP方法优化了3个联吡啶钌配合物[Ru(Htcterpy)X3]3-[tcterpy=4,4',4"-tricarboxy-2,2'∶6',2"-terpyridine, X=NCS(1), CN(2), Cl(3)]的基态几何结构, 得到的几何参数与实验结果吻合得很好. 采用TD-DFT方法, 得到了配合物1~3在气态和溶液(乙醇溶液和水溶液)中的激发态电子结构和电子吸收光谱. 利用SCRF方法中的CPCM模型来模拟溶剂化效应. 研究结果表明, 配合物1~3在气态和溶液中的吸收跃迁性质相似, 低能吸收均被指认为MLCT和LLCT的混合跃迁, 高能吸收均被指认为三联吡啶配体内的π→π*跃迁. 溶剂化效应使配合物1~3在溶液中的吸收光谱蓝移.     

双膦配合物Ru（OAc）_2（Ph_3P）（dppe）和Ru（OAc）_2（dppe）_2的设计合成、表征和氢化性能

Ｒｕ（ＯＡｃ）_２（Ｐｈ_３Ｐ）_２和１或２摩尔的双－（二苯基膦）乙烷（ｄｐｐｅ）在回流的甲苯中反应，分别生成双膦配位的Ｒｕ（ＯＡｃ）_２（Ｐｈ_３Ｐ）（ｄｐｐｅ）和Ｒｕ（ＯＡｃ）_２（ｄｐｐｅ）_２。并进行了元素分析、ＩＲ、ＮＭＲ等谱学表征。在温度－５０至４０℃的范围内，测定了Ｒｕ（ＯＡｃ）_２（Ｐｈ_３Ｐ）（ｄｐｐｅ）的￣（３１）Ｐ｛￣１Ｈ｝ＮＭＲ谱，讨论了配合物中膦配体的配位状态。在反应温度３０至９０℃、氢压１．０至５．０ＭＰａ的条件下，考察了两个配合物均相催化丙烯酸和苯乙烯的氢化性能。结果表明，题示的两个配合物是催化丙烯酸和苯乙烯氢化的有效催化剂。     

Ru(Ⅱ)和Ru(Ⅲ)配合物[Ru(bpy)(PH3)(-C≡CC6H4NO2-p)Cl]m(m=0,+1)的光谱性质的密度泛函-含时密度泛函理论研究

我们利用DFT中的B3LYP方法优化了Ru(Ⅱ)配合物和氧化的Ru(Ⅲ)配合物[Ru(bpy)(PH3)(-C≡CC6H4NO2-p)Cl]m[bpy=2,2′-bipyridine;m=0(1), 1(1 )]的基态几何结构,得到的几何参数与实验结果吻合的很好。采用TDDFT方法,得到了配合物1和1 的激发态电子结构和电子吸收光谱。研究结果表明,配合物1和1 随着氧化过程的发生,光谱性质也发生变化,Ru(Ⅱ)配合物的低能吸收被指认为MLCT/LLCT混合跃迁,而氧化的Ru(Ⅲ)配合物1 的低能吸收具有LMCT跃迁性质。     

配合物[M(CO)3(PPh2py)2](M=Fe,Ru)异构体的理论研究

对PPh2py配合物[M(CO)3(PPh2py)2](M=Fe, Ru)的三种构型的异构体1-6进行了研究. 其中PPh2py以两个P原子与M配位形成HH构型1(Fe)和4(Ru), 以一个P和一个N原子与M配位形成HT构型2(Fe)和5(Ru), 以两个N原子与M配位形成HH’构型3(Fe)和6(Ru). 结果表明, (1) PPh2py中P原子对HOMO轨道的贡献最大, PPh2py作为电子给体时易以P原子与金属原子结合. (2)从分子能量和相互作用能数据表明, 配合物中HH构型最稳定, HH'构型最不稳定, 这与合成产物为HH构型的结果一致. (3) 键长和Wiberg键级均表明P—M键比N—M键结合力强. P、M原子间存在σ键, 而N、Fe原子间仅存在nN→n*M或nN→σ*M-P的电荷转移作用. (4) HH构型中M对HOMO的贡献最大, PPh2py向M的电荷转移最强, 使M的负电荷最大, 故HH构型最易作为电子给体以M原子与第二个金属配位形成双核配合物.     

[Ru（MeIm）4L]^2＋（L=iip，tip，2ntz）的电子结构、DNA-键合、构效关系及光谱特征

采用密度泛函的方法,结合导体极化连续模型研究了水溶性二价钌．甲基咪唑类配合物[Ru（MeIm）4iip]^2＋。（1）、[Ru（MeIm）4tip]^2＋0＋（2）和[Ru（MeIm）42ntz]^2＋（3）的电子结构、DNA的键合倾向及构效关系,在水溶液中几何优化的基础上分析了配合物的电子结构特征,并合理解释了配合物与DNA的键合倾向．计算结果表明,在主配体上用噻吩代替咪唑取代基可以有效提高配合物与DNA的键合力;同时,在主配体的骨架上引入强电负性的N原子及NO2基团可以明显降低配合物最低未占据分子轨道能量及前沿分子轨道能量差．基于以上计算结果,预测所设计的配合物3具有最大的DNA键合力常数．另外,详细分析了配合物1、2的构效关系及抗肿瘤作用机理,并预测了配合物3的抗肿瘤活性．最后,用含时密度泛函方法对配合物的电子吸收光谱进行了计算和模拟,并与实验结果进行了对比分析．     

[Ru(bpy)_2tpphz]~(2+)与Zn~(2+)形成的双核配合物的荧光性质研究

近年来,钌多吡啶配合物与DNA的作用得到了比较广泛的研究,并且发展了一系列具有特定功能的钌配合物犤1犦。如传统的DNA分子光开关犤Ru(bpy)2dppz犦2+和犤Ru(phen)2dppz犦2+犤2,3犦(bpy=2,2'-联吡啶,phen=1,10-菲咯啉,dppz=二吡啶犤3,2-a:2',3'-c犦吩嗪)。这些配合物与DNA具有较强的结合力,在水溶液中几乎不发光,但在DNA存在下则有强烈荧光发出。这是由于配合物插入DNA的碱基对之后,保护了dppz的吡嗪环上的N原子,使其免受水分子的进攻从而导致配合物荧光的恢复。但是对于大多数的多吡啶钌配合物来讲,由于其自身较强的背景荧光或与DN…     

Synthesis,Structure and Electrochemistry of Triruthenium Cluster Complex [Ru_3(μ_3- O)(μ-CH_3CO_2)_6(py)_2(PPh_2py)](PF_6)·CH_2Cl_2

1 INTRODUCTION The transition metal cluster complexes exhi- biting multistep redox processes have attracted more and more attention because of their potential applications in the areas of photonic and electronic devices[1～4]. The oxo-centered carboxyla…     

C60Ru(OCOCF3)(CO)(PPh3)配合物的合成及性能

富勒烯;钌配合物;循环伏安法;C60Ru(OCOCF3)(CO)(PPh3)配合物的合成及性能