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Saccharified Uranyl Ions: Self-Assembly of UO₂ ²⁺ into Trinuclear Anionic Complexes by the Coordination of Glucosamine-Derived Schiff Bases.

ABSTRACT: The reaction of UO₂ (OAc)₂ ⋅ 2H₂ O with the biologically inspired ligand 2-salicylidene glucosamine (H₂ L¹ ) results in the formation of the anionic trinuclear uranyl complex [(UO₂ )₃ (μ₃ -O)(L¹ )₃ ]^2- (1^2- ), which was isolated in good yield as its Cs-salt, [Cs]₂ 1. Recrystallization of [Cs]₂ 1 in the presence of 18-crown-6 led to formation of a neutral ion pair of type [M(18-crown-6)]₂ 1, which was also obtained for the alkali metal ions Rb⁺ and K⁺ (M=Cs, Rb, K). The related ligand, 2-(2-hydroxy-1-naphthylidene) glucosamine (H₂ L² ) in a similar procedure with Cs⁺ gave the corresponding complex [Cs(18-crown-6)]₂ [(UO₂ )₃ (μ₃ -O)(L² )₃ ([Cs(18-crown-6)]₂ 2). From X-ray investigations, the [(UO₂ )₃ O(Lⁿ )₃ ]^2- anion (n=1, 2) in each complex is a discrete trinuclear uranyl species that coordinates to the alkali metal ion via three uranyl oxygen atoms. The coordination behavior of H₂ L¹ and H₂ L² towards UO₂ ²⁺ was investigated by NMR, UV/Vis spectroscopy and mass spectrometry, revealing the in situ formation of the 1^2- and 2^2- dianions in solution.

SUBMITTER: Schaper G

PROVIDER: S-EPMC8252515 | biostudies-literature |

REPOSITORIES: biostudies-literature

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UO2 2+-mediated ring contraction of pyrihexaphyrin: synthesis of a contracted expanded porphyrin-uranyl complex.

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