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Updated: Jun 21, 2025

Thermochemical Studies of NiII and ZnII Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Guest selectivity of [Ni2] supramolecular helicates
Manuel Imperato1,2,3, Alessio Nicolini1, Jordi Ribas-Ariño4
1Dipartimento di Scienze Chimiche e Geologiche e UdR INSTM, Università degli Studi di Modena e Reggio Emilia, via G. Campi 103, 41125 Modena, Italy. acornia@unimore.it.
Abstract:
Two new paramagnetic supramolecular helicates with the formula (X@[Ni2L3])3+ (X = Cl, or Br; L = a bis-pyrazolylpyridine ligand) have been prepared and are described. Helicates of this metal are very rare with virtually no prior examples of them acting as hosts of anionic species. The persistence of the new assemblies in solution has been demonstrated unambiguously by mass spectrometry and paramagnetic 1H NMR. This has allowed us to establish the preference of the coordination [Ni2] host for Cl- over Br-, in agreement with DFT calculations. These results show the promise of the use of metallohelicates as suitable systems for the selective encapsulation of specific anions in solution.
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