Iron β-diiminate Complexes with As-, As- and As-ligands

Different substituents at the β-diiminato ligand in low-valent [LFe(tol)] (L = β-diiminato) complexes fundamentally change their reactivity towards yellow arsenic. By using dmp (2,6-dimethylphenyl) as flanking groups, the tetranuclear complexes [(LFe)As] (L = L (1), L (2)) are isolated. For dipp (2,6-diisopropylphenyl) substituted ligands, dinuclear complexes [(LFe)(cyclo-As)] (L = L (3a), L (4a)) are obtained. Not only the choice of the ligand impacts the product formation, but also the temperature of the crystallization can shift their ratio in the solid state.