A Mn4 single-molecule magnet with the defective-dicubane structure from the use of pyrenecarboxylic acid

Reaction of 1-pyrenecarboxylic acid (pcH) and N-methyldiethanolamine (mdaH2) with MnII in CH2Cl2 or CHCl3 gives [Mn4(pc)4(mda)2(mdaH)2], possessing a defective-dicubane structure, as the ·2CH2Cl2 (3) and ·2CHCl3 (4) solvates, respectively. Magnetic data indicate 3 has an S = 8 ground state and is a single-molecule magnet. Complex 4 shows different magnetic behavior due to extensive π-π stacking and intermolecular exchange interactions.