Bimetallic lanthanide complexes of the calixarenes: europium(III) and tert-butylcalix[8]arene

Abstract

located 0.963 A from Pd.2. Crystals were grown from hexane solutions (-40 °C) and mounted in thin-walled glass capillaries under nitrogen. Unit cell parameters were obtained by carefully centering 25 reflections having 29 values between 24 and 28°. Examination of the diffraction symmetry and the systematic Registry No. 1, 111025-75-3; 2, 111025-74-2; [Pd(CO)Cl]", 28551-87-3; Pd, 7440-05-3. Supplementary Material Available: Tables of thermal parameters for 1 and 2 (2 pages); tables of structure factors for 1 and 2 (13 pages).Ordering information is given on any current masthead page.(14) P is used in the calculation of ( 7) to downweight intense reflections in the least-square refinement. The function minimized was > (| '0| -|F |)2, where w = 4(|F0|)2/[E(lf0|)2]2, where [ (| )2]2 = [S\C + R2B) + (7,(|/70|)2)2]/¿.2, where S2 is the scan rate squared, C is the total background count, R2 is the ratio of scan time to background count squared, and L? is the Lorentz-polarization factor. (15) See paragraph at end of paper regrading supplementary material.

Triple Inclusion by a Calixarene: the CrystaL Structure of the Europium(III) Complex of Bis(homooxa)‐p‐tert‐butylcalix[4]arene

“…As has been noted by others,["] the dissymmetric conformation adopted by p-tert-butylcalix [8]arene in several In this regard, it is notable that the position of the methyl group of these included solvent molecules is similar, relative to the calix rim, in all these complexes. The crystal structure of the present europium(II1) complex of bis(homooxa)-p-tert-butylcalix [4]arene (L 2)[' 'I shows the presence of a binuclear species (Fig. 1) similar to that found with L 1.…”

“…The crystal structure of the europium(n1) complex of pterr-butylcalix [4]arene (L l)['] shows a form of "double inclusion'' in which the metal ion is bound by phenoxide coordination and a molecule of dimethylformamide (DMF) solvent is included within the ligand "cup" possibly as a result of Van der Waals interactions between the solvent methyl groups and the ligand tBu substituents. The polar carbonyl moiety of DMF is directed out of the cup and away from the metal.…”

“…Seven-coordination , 3 la P i \ Scheme 1. The structure of the fully protonated ligand, bis(homooxa)-p-ferfbutylcalix [4]arene, L2. Component numbering as applied in the complex ion structure (and used in the text) is indicated.…”

p‐tert‐Butylcalix[8]arene: An Extremely Versatile Platform for Cluster Formation

“…p ‐ tert ‐Butylcalix[8]arene (TBC[8]) is significantly more flexible than TBC[4] due to annular inversion, and metal complexes6 (TM and Ln) formed with this ligand most frequently adopt three particular conformations: pleated‐loop,6c, e, f, i, j, l, o, p, v double‐cone,6a, b, q, s–u and a third in which the molecule wraps around a small cluster in a manner akin to the shell of a tennis ball 6d. h, k–n With respect to Ln TBC[8] complexes (there are only ten in total in the Cambridge Structural Database),7 one mononuclear complex has been reported in which the calixarene adopts a pleated‐loop conformation 6o.…”

Dreifacher Einschluß durch ein Calixaren: Struktur des Europium(III)‐Komplexes von Bis(homooxa)‐p‐tert‐butylcalix[4]aren

“…Die Struktur des Europium(n1)-Komplexes von p-tert-Butylcalix [4]-aren (LI)"] zeigt eine Form des ,,Doppeleinschlusses" : Das Metall-Ion ist an die Phenolatgruppen gebunden und ein Losungsmittelmolekuil Dimethylformamid (DMF) ist in der vom Ligand gebildeten Schale eingeschlossen, wahrscheinlich aufgrund von van-der-Waals-Wechselwirkungen zwischen den Methylgruppen des Losungsmittels und den tBu-Substituenten des Liganden. ''], selektiv aus einem Aceton/Acetonitril-Gemisch aufgenommen wird.…”