Diversified Two-Electron Reduction for Trivalent Scandium Complexes with Arene Ligands
Miaomiao Zhu, Tianyu Li, Zhengqi Chai, Junnian Wei, Ze-Jie Lv*, and Wen-Xiong Zhang*
Inorg. Chem. Front. 2023, 10, 630–637.
https://doi.org/10.1039/d2qi02123d
Reduced arene complexes of rare-earth metals are of great interest and importance because of their unique reactivity mimicking low-valent rare-earth metal species. Here, we present the synthesis and structural characterization of a series of reduced naphthalene or anthracene complexes of mononuclear scandium with the mixed C5Me5 (Cp*) and amidinate ligands. Among them, the reduced anthracene complexes of mononuclear scandium have been found for the first time to undergo rapid inter-ring rearrangement. Significantly, a reduced anthracene complex with scandium center attached to the terminal six-membered ring of anthracene was synthesized by modulating the substituents on amidinate ligand. The diversified two-electron redox reactions of the reduced naphthalene complex of mononuclear scandium toward cyclooctatetraene (COT), dibenzo[a,e]cyclooctene, benzophenone, 1,4-diazabutadiene (DAD), isothiocyanate, and selenium were examined. The scope of two-electron redox reaction via the trivalent scandium complex with the mixed Cp*/amidinate/arene ligand system is significantly expanded, thus these results remedy the shortcomings that rare-earth complexes are difficult to undergo the two-electron redox process.