Development of systematic synthetic method for iridium dimer complexes

铱二聚体配合物系统合成方法的开发

• 批准号: 11640560
• 负责人: EBIHARA Masahiro
• 金额: $ 2.11万
• 依托单位: Gifu University (2000)Okazaki National Research Institutes (1999)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11640560/
• 关键词: lantern-type complex; iridium; acetato bridge; crystal structure; ESR; redox; metal-metal bond

A bis (μ-acetato) dicarbonyldichlorodiiridium (II) complex, [Ir_2(μ-O_2CMe)_2Cl_2(CO)_2]1, was prepared by the one-step reaction of H_2IrCl_6 with MeCO_2Li under O_2 in a mixture of acetic acid and acetic anhydride. Dissolution of 1 into various ligating solvents gave [Ir_2(μ-O_2CMe)_2Cl_2(CO)_2L_2] (L=McCN : 2, dmso : 3, py : 4, 4-isopropylpyridine : 5). X-ray structure determinations of 2, 3 and 4 gave the Ir-Ir distances of 2.569 (1), 2.5980 (5) and 2.5918 (5) Å, respectively, which are in the range of the reported Ir (II)-Ir (II) single-bond distances. CV of 2, 4 and 5 exhibited a one-electron quasi-reversible oxidation wave at E_<1/2> of 1.30, 0.97 and 0.94 Vvs Fc^+/Fc, respectively. Bis (μ-acetato) dichlorodicarbonyldiiridium (II) complexes with group 15 compounds as the axial ligands, [Ir_2(μ-O_2CMe)_2Cl_2(CO)_2L_2] (L=PPh_36, PCy_37, P (OPh)_38, AsPh_39, SbPh_310) were synthesized. The Ir-Ir distances were longer than those of 2-4. The complexes had a chemically reversible one- … More electron oxidation wave of which E_<1/2> values were between 0.21 of 7 and 0.75 V of 8 depending on their axial ligands. The ESR spectra of 6^<+ >, 7^<+ > and 9^<+ > at 77 K were pseudoaxially symmetric. Their hyperfine splitting indicates that their odd electron is delocalized equivalently onto the two axial phosphorous or arsenic atoms. The odd electron densities were estimated from the hyperfine coupling tensors as ρ【approximately equal】0.1 on the P atom of 6^<+ > and 7^<+ > and ρ【approximately equal】0.15 on the As atom of 9^<+ >. These ESR results indicate that their SOMO is the σ_<IrIr> orbital with σ_<IrP>^* or σ_<IrAs>^* character. DFT calculations of model complexes, [Ir_2(μ-O_2CH)_2Cl_2(CO)_2(PH_3)_2]^<+ > and [Ir_2(μ-O_2CH)_2Cl_2(CO)_2(AsH_3)_2]^<+ >, gave an electronic structure consistent with the ESR results. Similar DFT calculatiouts of [Ir_2(μ-O_2CH)_2Cl_2(CO)_2(py)_2]^<+ > gave results that its odd electron is accommodated in the orbital with σ_<IrIr>, σ^*_<IrN> and π_<IrCr>^* character. This calculated result, however, is not consistent with the previously reported results of the ESR study of [Ir_2(μ-O_2CMe)_2Cl_2(CO)_2(py)_2]^<+ >. Less

以H_2IrCl_6与MeCO_2Li在O_2气氛下，乙酸和乙酸酐的混合物中一步反应制备了双(μ-乙酰基)二羰基二氯二铱(II)配合物[Ir_2(μ-O_2CMe)_2Cl_2(CO)_2]1。将1溶解到各种连接溶剂中得到[Ir_2(μ-O_2CMe)_2Cl_2(CO)_2L_2](L=McCN:2，dmso:3，py:4，4-异丙基吡啶：5)。 2、3和4的X射线结构测定得出Ir-Ir距离分别为2.569 (1)、2.5980 (5)和2.5918 (5) Å，位于报道的Ir (II)-Ir (II)单键距离范围内。 2、4和5的CV在E_1/2处分别表现出1.30、0.97和0.94Vvs Fc^+/Fc的单电子准可逆氧化波。合成了以15族化合物为轴向配体的双(μ-乙酰)二氯二羰基二铱(II)配合物[Ir_2(μ-O_2CMe)_2Cl_2(CO)_2L_2](L=PPh_36, PCy_37, P(OPh)_38, AsPh_39, SbPh_310)。 Ir-Ir距离比2-4更长。该配合物具有化学可逆的单电子氧化波，其 E_<1/2> 值在 7 的 0.21 和 8 的 0.75 V 之间，具体取决于其轴向配体。 6^+、7^+和9^+在77K时的ESR谱是赝轴对称的。它们的超精细分裂表明它们的奇数电子等效地离域到两个轴向磷或砷原子上。根据超精细耦合张量估计奇电子密度，在 6^<+ > 和 7^<+ > 的 P 原子上为 ρ【约等于】0.1，在 9^<+ > 的 As 原子上为 ρ【约等于】0.15。这些 ESR 结果表明，它们的 SOMO 是具有 σ_<IrP>^* 或 σ_<IrAs>^* 特征的 σ_<IrIr> 轨道。模型配合物 [Ir_2(μ-O_2CH)_2Cl_2(CO)_2(PH_3)_2]^<+ > 和 [Ir_2(μ-O_2CH)_2Cl_2(CO)_2(AsH_3)_2]^<+ > 的 DFT 计算给出了与 ESR 结果一致的电子结构。 [Ir_2(μ-O_2CH)_2Cl_2(CO)_2(py)_2]^<+>的类似DFT计算得出其奇数电子容纳在具有σ_<IrIr>、σ^*_<IrN>和π_<IrCr>^*特征的轨道中。然而，该计算结果与之前报道的[Ir_2(μ-O_2CMe)_2Cl_2(CO)_2(py)_2]^<+ >的ESR研究结果并不一致。较少的

项目成果

T.Kawamura: "δ_<MM>^*-π_L Odd Electron Delocalization onto Aromatic Bridging Ligands in a Paramagnetic Dirhodium Complex and Intermolecular π-Stack Interaction in Crystal"Bull.Chem.Soc.Jpn.. Vol.73. 657-668 (2000)

T.Kawamura：“δ_<MM>^*-π_L 奇数电子离域到顺磁性铑配合物中的芳香桥配体和晶体中的分子间 π 堆叠相互作用”Bull.Chem.Soc.Jpn.. Vol.73。 (2000)

T.Kawamura: "δ_<MM>*-π_L Odd Electron Delocalization onto Aromatic Bridging Ligands in a Paramagnetic Dirhodium Complex and Intermolecular π-Stack Interaction in Crystal"Bulletin of the Chemical Society of Japan. 73. 657-668 (2000)

T. Kawamura：“δ_<MM>*-π_L 奇数电子离域到顺磁性铑配合物中的芳香桥配体和晶体中的分子间 π 堆叠相互作用”日本化学学会公报 73. 657-668 (2000)。

Naohiro Kanematsu: "A one-step synthesis of an Ir (II) dinuclear complex. Preparation, structures and properties of bis (μ-acetato) dichlorodicarbonyl-diiridium (II) complexes"J.Chem.Soc., Dalton Transaction. 4413-4417 (1999)

Naohiro Kanematsu：“Ir (II) 双核络合物的一步合成。双 (μ-乙酰) 二氯二羰基-二铱 (II) 络合物的制备、结构和性质”J.Chem.Soc.，Dalton Transaction 4413-。 4417 (1999)

T.Kawamura: "δ_<MM>^*-π_L Odd Electron Delocalization onto Aromatic Bridging Ligands in a Paramagnetic Dirhodium Complex and Intermolecular π-Stack Interaction in Crystal"Bulletin of the Chemical Society of Japan. 73. 657-668 (2000)

T. Kawamura：“δ_<MM>^*-π_L 奇数电子离域到顺磁性铑配合物中的芳香桥配体和晶体中的分子间 π 堆叠相互作用”日本化学学会公报 73. 657-668 (2000)。