Tubelike Uranyl–Phenylenediacetate Assemblies from Screening of Ligand Isomers and Structure-Directing Counterions
Résumé
Reaction of 1,2-1,3-, or 1,4-phenylenediacetic acids (1,2-1,3-, or 1,4-H$_2$PDA) with uranyl ions under solvo-hydrothermal conditions and in the presence of [M(L)$_n$]$^{q+}$ cations, in which M = transition metal cation, L = 2,2-bipyridine (bipy) or 1,10-phenanthroline (phen), $n$ = 2 or 3, and $q$ = 1 or 2, gave ten complexes which have been crystallographically characterized. The diacetate ligands are bis-chelating and the uranyl cations are tris-chelated in all cases. [UO$_2$(1,2-PDA)$_2$Zn(phen)$_2$]⋅2H$_2$O (1) and [UO$_2$(1,4-PDA)$_2$Mn(bipy)$_2$]⋅H$_2$O (2) are heterometallic, neutral one-dimensional (1D) coordination polymers in which the carboxylate-coordinated 3d block metal cation is either decorating only (1), or participates in polymer building (2). [Zn(phen)$_3$][(UO$_2$)$_2$(1,3-PDA)$_3$] (3) and [Ni(phen)$_3$][(UO$-2$)$_2$(1,4-PDA)$_3$]⋅H$_2$O (4), with separate counterions, crystallize as anionic two-dimensional (2D) networks, as does [Cu(bipy)$_2$][H$_2$NMe$_2$][(UO$_2$)$_2$(1,4-PDA)$_3$] (5), which displays parallel 2D interpenetration. The complex [Zn(phen)$_3$][(UO$_2$)$_2$(1,2-PDA)$_3$]⋅7H$_2$O (6) crystallizes as a ladderlike, slightly inflated ribbon. The same topology is found in [Zn(bipy)$_3$][(UO$_2$)$_2$(1,3-PDA)$_3$] (7), but the larger separation between coordination sites and the coexistence of curved and divergent ligand conformations produce a tubelike assembly. An analogous, but more regular and spacious tubular geometry is found in [M(bipy)$_3$][(UO$_2$)$_2$(1,4-PDA)$_3$] with M = Co (8) or Ni (9), and {$\Lambda$-[Ru(bipy)$_3$]}[(UO$_2$)$_2$(1,4-PDA)$_3$] (10). The disordered counterions in 8 and 9 are replaced by well-ordered, enantiomerically pure chiral counterions in 10. The tubular assemblies formed in 7-10 are characterized by an oblong section and the presence of gaps in the walls, which enable the inclusion of two rows of counterions in the cavity
Origine | Fichiers produits par l'(les) auteur(s) |
---|
Loading...