Comparing the Electronic Structure of Iron, Cobalt, and Nickel Compounds That Feature a Phosphine-Substituted Bis(imino)pyridine Chelate
Comparing the Electronic Structure of Iron, Cobalt, and Nickel Compounds That Feature a Phosphine-Substituted Bis(imino)pyridine Chelate
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比较具有膦取代双（亚氨基）吡啶螯合物的铁、钴和镍化合物的电子结构
DOI：
10.1021/acs.inorgchem.2c00008
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发表时间：
2022
影响因子：
4.6
通讯作者：
Baik, Mu-Hyun
中科院分区：
文献类型：
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作者：
Mena, Matthew R.;Kim, Jun-Hyeong;So, Sangho;Ben-Daat, Hagit;Porter, Tyler M.;Ghosh, Chandrani;Sharma, Anuja;Flores, Marco;Groy, Thomas L.;Baik, Mu-Hyun
最近发现，（Ph 2 PPrPDI）Mn（PDI =吡啶二亚胺）存在的低自旋Mn（II），这是支持的PDI二价阴离子和中间自旋Mn（II）的反铁磁耦合到三重态PDI二价阴离子，一个发现，鼓励后期的第一行金属变体，具有相同的螯合物的合成和电子结构评估的叠加。将Ph 2 PPrPDI加入到FeBr 2中，导致溴化物解离并形成[（Ph 2 PPrPDI）FeBr][Br]。使用过量的钠汞齐还原该前体得到（Ph 2 PPrPDI）Fe，其具有由双阴离子PDI配体支撑的Fe（II）中心。同样，还原的预混合溶液的Ph 2 PPrPDI和CoCl 2产生的钴类似物，（Ph 2 PPrPDI）Co。EPR光谱和密度泛函理论计算表明，该化合物具有高自旋Co（I）中心，是反铁磁耦合到PDI自由基阴离子。Ph_2PPrPDI与Ni（COD）_2的加成反应导致配体置换，形成了具有膦侧基的（Ph_2PPrPDI）Ni。单晶X射线衍射、CASSCF计算和EPR光谱表明，（Ph 2 PPrPDI）Ni最好描述为具有Ni（II）-PDI 2-构型。这些化合物之间的电子差异突出显示，和计算分析ofPh 2 PPrPDI denticity揭示了热力学处罚与膦解离从5-坐标（Ph 2 PPrPDI）Mn，（Ph 2 PPrPDI）Fe，和（Ph 2 PPrPDI）Co。
It was recently discovered that (Ph2PPrPDI)Mn (PDI = pyridine diimine) exists as a superposition of low-spin Mn(II) that is supported by a PDI dianion and intermediate-spin Mn(II) that is antiferromagnetically coupled to a triplet PDI dianion, a finding that encouraged the synthesis and electronic structure evaluation of late first row metal variants that feature the same chelate. The addition ofPh2PPrPDI to FeBr2resulted in bromide dissociation and the formation of [(Ph2PPrPDI)FeBr][Br]. Reduction of this precursor using excess sodium amalgam afforded (Ph2PPrPDI)Fe, which possesses an Fe(II) center that is supported by a dianionic PDI ligand. Similarly, reduction of a premixed solution ofPh2PPrPDI and CoCl2yielded the cobalt analog, (Ph2PPrPDI)Co. EPR spectroscopy and density functional theory calculations revealed that this compound features a high-spin Co(I) center that is antiferromagnetically coupled to a PDI radical anion. The addition ofPh2PPrPDI to Ni(COD)2resulted in ligand displacement and the formation of (Ph2PPrPDI)Ni, which was found to possess a pendent phosphine group. Single-crystal X-ray diffraction, CASSCF calculations, and EPR spectroscopy indicate that (Ph2PPrPDI)Ni is best described as having a Ni(II)-PDI2–configuration. The electronic differences between these compounds are highlighted, and a computational analysis ofPh2PPrPDI denticity has revealed the thermodynamic penalties associated with phosphine dissociation from 5-coordinate (Ph2PPrPDI)Mn, (Ph2PPrPDI)Fe, and (Ph2PPrPDI)Co.