Lanthanide complexes 2,2 :6 ,2”-terpyridyl

Figure 2 Structure of the cation of [Pra(terpyridyl)(H20)s]Cl2-3H20. The structure of this complex would have been impossible to establish by other means than Effraction, and the same is true for many other lanthanide complexes, owing to the lanthanides great variety of coordination patterns (Reproduced with permission from ref. 165. Copyright,...

Senechal-David K, Hemeryck A, Tancrez N, Toupet L, AG WJ, Ledoux I, Zyss J, Boucek-kine A, Guegan J-P, Le Bozec H, Maury O (2006) Synthesis, structural studies, theoretical calculations, and linear and nonlinear optical properties of terpyridyl lanthanide complexes new evidence for the contribution of f electrons to the NLO activity. J Am Chem Soc 128 12243-12255... 

Radonovich and Click [156) in 1971 reported the crystal structure of Pr(terp)Cl3 8H2O complex, which they prepared by the original method of Sinha [157), for the preparation of mono-terpyridyl-lanthanide(III) chlorides, [M(terp)Cl3 wHaO], where terp =2,2, 2"-terpyridyl and has the following structure. When... 

The lanthanide trifluoromethylsulfonates M(CF3S03)3 have been prepared and their complexes with pyo and bpyo have been prepared in ethanol or ethanol/triethylformate and examined. Complexes [M(pyo)g](CF3S03)3 and [M(bpyo)4](CF3S03)3 (M = La, Nd, Eu or Ho in each case) were obtained and results indicated that the anions were not coordinated.304,305 A number of complexes of pyo, bpyo and 2,2, 6, 2"-terpyridyl-JV,lV, iV"-trioxide (tpyo) with... 

Terpyridyl is a terdentate ligand and behaves like bipyridyl, and o-phenanthroline. The three terpyridyl ligands coordinate to the lanthanide when the anion is perchlorate. The emission spectrum of the Eu(III) complex points to D3 symmetry which has been confirmed by the determination of the structure [242],... 

Tridentate N-donor ligands are efficient in separating actinides from lanthanides selectively by solvent extraction, an area of potential great importance in treatment of used nuclear fuel rods. The tridentate ligand 2,2 6 ,2 -terpyridyl (terpy) forms a range of complexes. The perchlorate complexes [Ln(terpy)3] ( 104)3 contain nine-coordinate cations with near- )3 symmetry, a structure initially deduced from the fluorescence spectrum of the europium compound (Section 5.4) and subsequently confirmed by X-ray diffraction smdies (Figure 4.7)... 

Complexes of the lanthanides with the rather similar terdentate hgands 2,2 6, 2"-terpyridyl (terpy), 2,4,6-tris-2-pyridyl-l,3,5-triazine (tptz), 4-amino-bis(2,6-(2-pyridyl))-1,3,5-triazine (abptz), and related ligands have been studied iu cousiderable detail aud uumber, as these terdentate N-donor ligands are efficient in separating actinides from lanthanides selectively by solvent extraction, of obvious relevance to processing nuclear waste. 

Mono- or dinuclear platinum(II) complex capped with one or two [Pt(Bu3tpy)]+ units can be incorporated with Ln(hfac)3 units to produced a series of PtLn (Ln = Nd 88, Yb 89) and Pt2Ln (Ln = Nd 90, Yb 91) heteronuclear complexes [131]. With excitation at 350 nm < L < 550 nm, sensitized NIR lanthanide luminescence was detected in these Pt-Ln heteronuclear complexes with microsecond ranges of lifetimes, whereas Pt-based luminescence from the MLCT and LLCT states was mostly quenched. This reveals that fairly effective Pt Ln energy transfer is operating from the platinum(II) terpyridyl alkynyl chromophores to the lanthanide(III) centers. 

Li, X.-L., Shi, L.-X., Zhang, L.-Y, et al (2007) Syntheses, structures, and sensitized lanthanide luminescence by Pt- Ln (Ln = Eu, Nd, Yb) energy transfer for heteronuclear PtLn2 and R2Ln4 complexes with a terpyridyl-functionalized alkynyl ligand. Inorganic Chemistry, 46, 10892. 

For the better part of two decades, the chemistry of self-assembled systems containing lanthanides has been dominated by hehcate systems [20, 21]. Simple tridentate ligands such as 2,6-dipicolinate, terpyridyl and 6-(diaminocarbonyl)-picolinic acid form stable and luminescent triple helicate complexes in water [21-24]. Polymetallic chelates can be assembled by using related ligand structures that can bridge between two metal centres. 

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