Magnetic properties of intramolecularly hydrogen-bonded carboxylate copper(II) dimer complexes

Abstract

Novel copper(II) dimer complexes, [Cu₂{OCOC₆H₃Me-2-(NHCOBu^t)-6}₄(MeOH)(H₂O)] and [Cu₂{OCOC₆H₃(NHCOBu^t)₂-2,6}₄(MeCN₂)], containing bulky, intramolecularly NH⋯O hydrogen-bonded carboxylate ligands, are synthesized; the former shows a distorted Cu–O–C–O–Cu structure with a magnetic exchange (–2J= 302 cm^–1) between the two Cu^II ions while the latter has a twisted Cu–O–C–O–Cu structure with a relatively large exchange (–2J= 460 cm^–1) through the NH⋯O hydrogen bonds.