2026-04-13T13:17:58Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1618852025-12-05T14:33:14Zcom_2072_1057col_2072_478917col_2072_478923

00925njm 22002777a 4500 dc Mayans Ayats, Júlia author Font Bardia, Ma. Mercedes author Di Bari, Lorenzo author Arrico, Lorenzo author Zinna, Francesco author Pescitelli, Gennaro author Escuer Fité, Albert author 2020-05-21T09:02:05Z 2020-05-21T09:02:05Z 2018-05-28 2020-05-21T09:02:05Z The systematic reactions of a family of tetradentate pyridyl/imine and quinolyl/imine racemic or enantiopure Schiff bases with Ni(NO3)(2) or Ni(ClO4)(2) in the presence of sodium azide yielded, as a function of the starting racemic, chiral or achiral base, a set of chiral, meso or achiral complexes. In all cases, the compounds consist of two Ni-II cations linked by a double azido bridge in its end-on coordination mode. All the dimers exhibit a mesocate supramolecular structure and one of them, the unprecedented mix of helicate and mesocate in 2:1 ratio. The transition from mesocate to helicate conformation has been reached by tuning the flexibility of the central spacers of the Schiff bases and the size of the substituents. Electronic circular dichroism (ECD) studies have been performed for two pairs of enantiomers and interpreted by means of DFT calculations. Susceptibility measurements show a ferromagnetic coupling between the Ni-II cations mediated by the end-on azido bridges. Níquel Magnetisme Nickel Magnetism From Mesocates to Helicates: Structural, Magnetic and Chiro-Optical Studies on Nickel(II) Supramolecular Assemblies Derived from Tetradentate Schiff Bases