Alkali Metal Reduction of 1,2-Bis[(2,6-dibenzhydryl-4-methylphenyl)imino]acenaphthene (ArBIG-bian) to Radical-Anion

Reduction of Ar-BIG-bian (1, 1,2-bis[(2,6-dibenzhydryl-4-methylphenyl)imino]acenaphthene) with one molar equivalent of Li, Na or K in tetrahydrofuran (THF) affords corresponding radical-anionic salts (Ar-BIG-bian)M(THF) (M=Li, 2; Na, 3; K, 4). Compounds 2-4 were isolated in good yields and characterized by the elemental analysis, IR and ESR spectroscopy as well as the single-crystal X-Ray analysis. Bulky Ph-2(H)C groups in Ar-BIG-bian ligand prevent dimerization of complexes 2-4 and limit a number of coordinated THF molecules to one. In all three products a saturation of the alkali metal coordination sphere is achieved through an interaction with Ph rings of Ph-2(H)C substituents.