Multiple aspects of chirality in coordination polymers formed by the uranyl ion with (1R,3S)-(+)-camphorate ligands

Pierre Thuéry (1) , Jack Harrowfield (2)

1 LCMCE - Laboratoire de Chimie Moléculaire et de Catalyse pour l'Energie (ex LCCEF)
2 ISIS - Institut de Science et d'ingénierie supramoléculaires

Following previous work on complexes of the anions of (1R,3S)-(+)-camphoric acid (H$_2$cam) with the uranyl cation, three novel species have been synthesized under solvo-hydrothermal conditions. [UO$_2$(Hcam)$_2$(4,4ʹ-bipy)] (1), where 4,4ʹ-bipy is 4,4ʹ-bipyridine, crystallizes as a monoperiodic polymer with bridging 4,4ʹ-bipy molecules and chelating, terminal Hcamanions, hydrogen bonding between carboxylic and carboxylate groups in adjacent chains giving diperiodic networks. [UO$_2$(cam)(2,2ʹ-bipy)] (2), where 2,2ʹ-bipy is 2,2ʹ-bipyridine, crystallizes also as a monoperiodic polymer, but bis-chelating cam 2anions are here bridging and the chelating 2,2ʹ-bipy ligands induce chirality at the uranium centres; the chains are helical, left-or right-handed depending on the chirality of the associated uranium centres. [Zn(phen)$_3$][(UO$_2$)$_2$(cam)$_3$] (3), where phen is 1,10-phenanthroline, is an anionic diperiodic network with hcb topology displaying a grooved shape. In all three instances, the enantiomeric purity of the camphorate ligands does not produce significant enantioselectivity in regard to other aspects of the structural chirality.

Keywords: Uranyl Ion; Camphoric acid; Chiral coordination polymers

Domains: Cristallography; Coordination chemistry

Pierre Thuéry, Jack Harrowfield. Multiple aspects of chirality in coordination polymers formed by the uranyl ion with (1R,3S)-(+)-camphorate ligands. Polyhedron, 2022, 218, pp.115764. ⟨10.1016/j.poly.2022.115764⟩. ⟨cea-03607813⟩