A Pentanuclear Manganese Single-Molecule Magnet with a Large Anisotropy

The reaction of MnCl2·4H2O (1 equiv), salicyladoxime (H2salox) (1 equiv), and NaN3 (1 equiv) in MeOH with NEt4OH (1 equiv) gave (NEt4)3[Mn5O(salox)3(N3)6Cl2] (2) in ∼14% yield. Ferromagnetic exchange between the five Mn ions in 2 leads to an S = 11 ground state and is established as a new single-molecule magnet with an anisotropy energy, Ueff, of 40.3 K by frequency dependent out-of-phase alternating current susceptibility signals and temperature and sweep rate dependent hysteresis loops.