Spectroscopic, Magnetic, and Computational Investigations on a Series of Rhenium(III) Cyclopentadienide β-diketiminate Halide and Pseudohalide Complexes
Spectroscopic, Magnetic, and Computational Investigations on a Series of Rhenium(III) Cyclopentadienide β-diketiminate Halide and Pseudohalide Complexes
复制标题
对一系列环戊二烯铼β-二酮亚胺卤化物和拟卤化物配合物的光谱、磁学和计算研究
DOI：
10.1021/acs.organomet.1c00516
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发表时间：
2021
期刊：
影响因子：
2.8
通讯作者：
Arnold, John
中科院分区：
文献类型：
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作者：
Ouellette, Erik T.;Amaro Estrada, Jorge Ivan;Lussier, Daniel J.;Chakarawet, Khetpakorn;Lohrey, Trevor D.;Maron, Laurent;Bergman, Robert G.;Arnold, John
低价铼（I）盐Na[Re（η5-Cp）（BDI）]（BDI =N，N′-bis（2，6-diisopropylphenyl）-3，5-dimethyl-β-diketiminate）与各种卤化物和硫属元素化物反应，分离出一系列双（III）卤化物和−拟卤化物配合物：Re（X）（η5-Cp）（BDI）（1-X，X = F，Cl，Br，I;2，X = OTf）和Re（ER）（η5-Cp）（BDI）（3-ER，ER = SBn，SeBn，TePh）。这些配合物的1H NMR光谱显示出从典型的抗磁性区域偏移几ppm的尖锐共振，以及卤化物（除F外）和硫族化物系列的明显化学位移趋势，Cp和BDI主链峰随着原子序数的增加而向低场移动。随后对三卤代配合物1-Cl、1-Br和1-I的磁化率测量表明，这些配合物显示出与温度无关的顺磁性（TIP），其TIP值为7.41（44）× 10- 4 ~ 1.50（51）× 10- 3cm ~ 3 mol ~（-1）。多参考完全活性空间自洽场（CASSCF）计算结合自旋轨道状态混合显示热隔离基态和第一激发自旋轨道状态之间的小能量分离（1.7-3.0 kcal/mol）的卤化物，确认低位激发态是负责观察到的TIP行为。
The low-valent rhenium(I) salt Na[Re(η5-Cp)(BDI)] (BDI =N,N′-bis(2,6-diisopropylphenyl)-3,5-dimethyl-β-diketiminate) was shown to react with various halide and chalcogenolate reagents, leading to the isolation of a series of rhenium(III)–halide and −pseudohalide complexes: Re(X)(η5-Cp)(BDI) (1-X, X = F, Cl, Br, I;2, X = OTf) and Re(ER)(η5-Cp)(BDI) (3-ER, ER = SBn, SeBn, TePh). The1H NMR spectra of these complexes displayed sharp resonances shifted several ppm from typical diamagnetic regions, as well as distinct chemical shift trends down both the halide (with the exception of F) and chalcogenolate series, with both Cp and BDI backbone peaks moving downfield with increasing atomic number. Subsequent magnetic susceptibility measurements of the rhenium(III) halides1-Cl,1-Br, and1-Iindicated that these complexes display temperature-independent paramagnetism (TIP), with χTIPvalues of 7.41(44) × 10–4to 1.50(51) × 10–3cm3mol–1. Multireference complete active space self-consistent field (CASSCF) computations incorporating spin–orbit state mixing revealed small energy separations (1.7–3.0 kcal/mol) between thermally isolated ground states and the first excited spin–orbit states for the rhenium halides, confirming that low-lying excited states are responsible for the observed TIP behavior.