Institute of Inorganic Chemistry, University of Regensburg, 93040, Regensburg, Germany.
Chemistry. 2023 Jun 7;29(32):e202300459. doi: 10.1002/chem.202300459. Epub 2023 Apr 24.
The heterobimetallic triple-decker complex [(CpFe)(Cp'''Co)(μ,η : η -P )] (1) was functionalized by main group nucleophiles and subsequently electrophilically quenched or oxidized. Reacting 1 with group 14 nucleophiles revealed different organo-substituted P R middle-decks depending on the steric and electronic effects of the used alkali metal organyls (2: R=tBu; 3: R=Me). Further, with group 15 nucleophiles, the first structural characterized monosubstituted complexes with phosphanides could be obtained as P ligands containing exocyclic {PR } units (4: R=Cy, H; 5: R=Ph). These monoanionic complexes 2-5 were isolated and subsequent electrophilic quenching revealed novel types of neutral functionalized polyphosphorus complexes. These complexes bear formal chains of P R'R'' (6: R'=tBu, R'=Me) in a 1,3-disubstitution pattern or P R'R''R''' units (7: R'=Cy, R''=H, R'''=Me; 8: R'=Me, R''=Ph, R'''=Me) in a 1,1,3-substitution as middle-decks stabilized by one {Cp'''Co} and one {CpFe} fragment. One-electron oxidation of 2, 3 or 5 by AgBF gave access to paramagnetic triple-decker complexes bearing P R middle-decks in various coordination fashions (R=tBu (10), R=PPh (12)). Interestingly, for R=Me (11), a dimerization is observed revealing a diamagnetic tetranuclear cluster containing a unique dihydrofulvalene-type P R ligand. All complexes were characterized by crystallographic and spectroscopic methods (EPR, multinuclear NMR and mass spectrometry) and their electronic structures were elucidated by DFT calculations.
[(CpFe)(Cp'''Co)(μ,η : η -P )] 的杂核三三明治配合物（1）被主族亲核试剂官能化，随后被亲电试剂猝灭或氧化。用 14 族亲核试剂与 1 反应，根据所用碱金属有机化合物的空间位阻和电子效应，得到不同的有机取代的 P R 中间层（2：R=tBu；3：R=Me）。此外，用 15 族亲核试剂，可以获得第一个结构表征的单取代膦配合物，作为含有外环 {PR }单元的 P 配体（4：R=Cy，H；5：R=Ph）。这些单阴离子配合物 2-5 被分离出来，随后的亲电猝灭反应揭示了新型中性官能化多磷配合物。这些配合物带有形式的 PR'R''（6：R'=tBu，R'=Me）1,3-二取代链或 P R'R''R'''单元（7：R'=Cy，R''=H，R'''=Me；8：R'=Me，R''=Ph，R'''=Me）作为中间层，由一个 {Cp'''Co} 和一个 {CpFe} 片段稳定。通过 AgBF 对 2、3 或 5 的单电子氧化，得到了带有 P R 中间层的顺磁三三明治配合物，其配位方式各异（R=tBu（10），R=PPh（12））。有趣的是，对于 R=Me（11），观察到二聚化，揭示了一个含有独特二氢富勒烯型 P R 配体的反磁性四核簇。所有配合物均通过晶体学和光谱学方法（EPR、多核 NMR 和质谱）进行了表征，并通过 DFT 计算阐明了它们的电子结构。
