New dinuclear lanthanide(III) complexes based on 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione and 2,2′-bipyrimidine

Reaction of mononuclear Ln(fod)3 chelates (where fod is the anion of 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione and Ln = Nd, Eu, Tb and Lu) with potentially bridging ligand 2,2′-bipyrimidine (bpm) in 2:1 mole ratio in ethanol afforded new dinuclear lanthanide complexes of the form [Ln(fod)3-(μ-bpm)-Ln(fod)3]. Neodymium complex is one of the rare bipyrimidine-bridged dinuclear complexes. The absorption spectrum of the neodymium complex displays characteristic hypersensitive as well as non-hypersensitive transitions. The excitation of Eu–Eu and Tb–Tb complexes at 355 nm produces an intense red and green luminescence, respectively.