Dinuclear lanthanide(III) complexes containing β-diketonate terminal ligands bridged by 2,2′-bipyrimidine

Synthesis, visible light absorption and luminescence of bipyrimidine bridged dinuclear lanthanide complexes of 2,4-pantanedione

“…[17] and those of general formula [{Ln 2 (β-diketone) 6 }(µ-bpm)] [8,[18][19][20][21]. We have recently reported homo-and hetero-dinuclear trivalent lanthanide complexes of 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione (Hfod) bridged by bpm [9,22] and pyrazine (pyz) [23].…”

“…We have isolated and investigated 4f-4f absorption and hypersensitivity of many of these complexes [25][26][27]. A report by Swavey and co-workers that the reaction of acetylacetone, trivalent lanthanide chloride and bpm, in the presence of a base, failed to yield dinuclear or even mononuclear complexes [19], prompted us to investigate the synthesis of bpm bridged dinuclear complexes of tris(acetylacetonato)lanthanide(III). Thus, in an effort to see whether or not both the chelating ends of bpm coordinate with two units of coordinatively unsaturated Ln(acac) 3 and manifestation of this bonding on the properties of resulting complexes, ethanolic solutions of [Ln(acac) 3 (H 2 O) 2 ] (Ln = Nd, Sm, Eu and Er) and 2,2′-bipyrimidine were allowed to react in 2:1 molar ratio which yielded bpm bridged dinuclear complexes of the type [(acac) 3 Ln(μ-bpm)Ln(acac) 3 ].…”

“…The dinuclear bpm bridged lanthanide complexes are relatively limited in number. The structurally characterized homodinuclear complexes include [{(C 5 Me 5 ) 2 Eu} 2 (μ-bpm)] [15] [{Ln(NO 3 ) 3 (bpm)} 2 (μ-bpm)] [16] [Nd(NO 3 ) 3 (bpm)(MeOH) 2 ][17] and those of general formula [{Ln 2 (β-diketone) 6 }(µ-bpm)] [8,[18][19][20][21]. We have recently reported homo-and hetero-dinuclear trivalent lanthanide complexes of 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione (Hfod) bridged by bpm [9,22] and pyrazine (pyz) [23].…”

Monometallic europium, terbium, and neodymium complexes formed from the bridging ligand 2,3-bis(2-pyridyl)pyrazine: Crystal structure and temperature dependent luminescent properties

“…For example, due to the equivalent nitrogen atoms, dinuclear lanthanide complexes bridged by bpm display only a slight torsion angle and a greater degree of symmetry [13]. In addition we have found that lanthanide bimetallic complexes formed with bpm can be synthesized under mild conditions in relatively high yields [14]. The dpp ligand coordinates to lanthanide metals through pyrazine and pyridyl based nitrogen atoms.…”

Structural analysis and electronic properties of a homodinuclear erbium(III) complex bridged by the polyazine ligand 2,2′-bipyrimidine

“…In a previous study homodinuclear and mononuclear lanthanide complexes synthesized from lanthanide(III) salts, 2,2 0 -bipyrimidine, and a series of b-diketonates was described [7]. To ensure the enol form, the b-diketonates were first dissolved in a basic ethanol solution.…”