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The ligand N,N′ -ethylenebis(pyridin-2-one) (EBP) forms a range of lanthanide (Ln) complexes of types Ln(EBP) 2 (NO 3 ) 3 (Ln = La-Gd), Ln 2 (EBP) 3 (NO 3 ) 6 ·2MeOH (Ln=GdYb and also Y), Ln 2 (EBP) 3 (NO 3 ) 6 · n MeCN (Ln=TbYb), representative members of which have been studied by single crystal X-ray diffraction. Crystals of Eu(EBP) 2 (NO 3 ) 3 are monocline, space group C 2/ c , a =20.583(3). b = 9.453(2), c = 17.006(2) A , β = 120.58(2)°, Z = 4 . The compound is mononuclear with each Eu centre having a coordination environment comprising three chelating nitrates and two nine-membered chelate rings formed by the EBP ligands. Crystals of Tb 2 (EBP) 3 (NO 3 ) 6 ·5MeCN are triclinic, space group P Ī, a = 10.504(5), b = 10.854(4), c = 17.145(6) A , α = 84.23(2), β = 72.68(2), γ = 72.79(2)°, Z = 2 . The EBP ligands bridge the Tb centres forming sheets of contiguous 54-membered rings. The MeCN molecules of solvation are occluded within the lattice, some lying within the metallamacrocyclic rings and some between the sheets. Crystals of &{[Ho(EBP) 2 (MeOH)(NO 3 ) 3 ]0.5(EBP)&} 0 are triclinic, space group P Ī, a = 8.316(2), b = 10.138(2), c = 15.441(3) A , α = 92.82(2), β = 92.29(2), γ = 102.99(2)°, Z = 2 . Each Ho atom is coordinated to three chelating nitrate groups, two bridging EBP ligands and one methanol molecule leading to the formation of polymeric chains [Ho(EBP) 2 (MeOH)(NO 3 ) 3 ] 0 . The remaining EBP molecules are non-coordinated but form hydrogen bonds to the methanol ligands and thereby link adjacent chains to form sheets of contiguous 78-membered rings. |
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