Zarcone Samuel R, Zhang Zihan, Handunneththige Suhashini, Ni Zhen, Bhuvanesh Nattamai, Nippe Michael, Meyer Karsten, Hall Michael B, Gladysz John A
Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States.
Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstraße 1, 91058 Erlangen, Germany.
Inorg Chem. 2024 Sep 2;63(35):16313-16326. doi: 10.1021/acs.inorgchem.4c02275. Epub 2024 Aug 20.
UV irradiation of yellow CHCl solutions of -Fe(CO)(P((CH))P) () and PMe (10 equiv) gives, in addition to the previously reported dibridgehead diphosphine P((CH))P (46%), a green paramagnetic complex that crystallography shows to be the trigonal-bipyramidal iron(I) radical -[Fe(CO)(Cl)(P((CH))P)] (; 31% after workup). This is a rare example of an isolable species of the formula [Fe(CO)(L)(X)] ( = 0-3, L = two-electron-donor ligand; X = one-electron-donor ligand). Analogous precursors with longer P(CH)P segments ( = 12, 14, 16, 18) give only the demetalated diphosphines, and a rationale is proposed. The magnetic susceptibility of , assayed by Evans' method and SQUID measurements, indicates a spin () of /. Cyclic voltammetry shows that undergoes a partially reversible one-electron oxidation, but no facile reduction. The UV-visible, EPR, and Fe Mössbauer spectra are analyzed in detail. Complex is similarly studied, and, despite the extra valence electron, exhibits a comparable oxidation potential (Δ ≤ 0.04 V). The crystal structure shows a cage conformation, solvation level, disorder motif, and unit cell parameters essentially identical to those of . DFT calculations provide much insight regarding the structural, redox, and spectroscopic properties.
用紫外线照射黄色的 -Fe(CO)(P((CH))P) () 的 CHCl 溶液以及 10 当量的 PMe，除了先前报道的双桥头双膦 P((CH))P（产率 46%）外，还得到一种绿色顺磁性配合物，晶体学研究表明其为三角双锥构型的铁(I)自由基 -[Fe(CO)(Cl)(P((CH))P)] (; 后处理后产率 31%)。这是通式为 [Fe(CO)(L)(X)] （ = 0 - 3，L = 双电子供体配体；X = 单电子供体配体）的可分离物种的罕见实例。具有更长 P(CH)P 链段（ = 12、14、16、18）的类似前体仅生成脱金属的双膦，并给出了相应的解释。通过埃文斯方法和超导量子干涉仪测量测定的 的磁化率表明其自旋 () 为 /。循环伏安法表明 经历了部分可逆的单电子氧化，但没有容易的还原过程。对紫外可见光谱、电子顺磁共振光谱和铁穆斯堡尔光谱进行了详细分析。对配合物 也进行了类似研究，尽管有额外的价电子，但它表现出相当的氧化电位（Δ ≤ 0.04 V）。晶体结构显示其笼状构象、溶剂化水平、无序模式和晶胞参数与 的基本相同。密度泛函理论计算为其结构、氧化还原和光谱性质提供了很多见解。
