An Isolable Magnesium(II)-Radical Dianion Complex

Magnesium­(I) complexes have attracted a great deal of attention because of their practical application as elegant organic-soluble reducing agents in small-molecule activation and organometallic synthesis. However, no stable mononuclear magnesium­(I) compounds have been isolated so far. Herein, we used the ligand 3,6-di-tert-butyl-1,8-bis­(10-phenylanthracen-9-yl)­carbazolyl (L–) to synthesize the magnesium­(I) species, and the magnesium complex LMg­(THF)2 (3) was isolated. Electron paramagnetic resonance spectroscopic studies and theoretical calculations reveal that the unpaired electron mainly resides at one of the anthracenyl moieties, and 3 is essentially a magnesium­(II)-radical dianion complex.