Synthesis and ligand-based reduction chemistry of boron difluoride complexes with redox-active formazanate ligands

Mono(formazanate) boron difluoride complexes (LBF2), which show remarkably facile and reversible ligand-based redox-chemistry, were synthesized by transmetallation of bis(formazanate) zinc complexes with boron trifluoride. The one-electron reduction product [LBF2](-)[Cp2Co](+) and a key intermediate for the transmetallation reaction, the six-coordinate zinc complex (L(BF3))(2)Zn were isolated and fully characterized.