Maskey Rezisha, Bendel Christoph, Malzacher Jonas, Greb Lutz
Institute of Inorganic Chemistry, Ruprecht Karl University Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.
Chemistry. 2020 Dec 23;26(72):17386-17389. doi: 10.1002/chem.202004712. Epub 2020 Nov 24.
Quinones are mild oxidants, the redox potentials of which can be increased by supramolecular interactions. Whereas this goal has been achieved by hydrogen bonding or molecular encapsulation, a Lewis acid-binding strategy for redox amplification of quinones is unexplored. Herein, the redox chemistry of silicon tris(perchloro)dioxolene 1 was studied, which is the formal adduct of ortho-perchloroquinone Q with the Lewis superacid bis(perchlorocatecholato)silane 2. By isolating the anionic monoradical 1 , the redox-series of a century-old class of compounds was completed. Cyclic voltammetry measurements revealed that the redox potential in 1 was shifted by more than 1 V into the anodic direction compared to Q , reaching that of "magic blue" or NO . It allowed oxidation of challenging substrates such as aromatic hydrocarbons and could be applied as an efficient redox catalyst. Remarkably, this powerful reagent formed in situ by combining the two commercially available precursors SiI and Q .
醌类是温和的氧化剂，其氧化还原电位可通过超分子相互作用提高。虽然通过氢键或分子封装已实现这一目标，但醌类氧化还原放大的路易斯酸结合策略尚未得到探索。在此，研究了三（全氯）二氧杂环戊二烯硅1的氧化还原化学，它是邻全氯醌Q与路易斯超强酸双（全氯邻苯二酚根）硅烷2的形式加合物。通过分离阴离子单自由基1，完成了一类具有百年历史的化合物的氧化还原系列。循环伏安法测量表明，与Q相比，1中的氧化还原电位向阳极方向移动了超过1 V，达到了“魔蓝”或NO的电位。它能够氧化芳烃等具有挑战性的底物，并可作为一种高效的氧化还原催化剂。值得注意的是，这种强大的试剂是通过将两种市售前体SiI和Q原位形成的。
