Spontaneous Chiral Resolution of a MnIII Spin‐Crossover Complex with High Temperature 80 K Hysteresis

Abstract

AbstractNon‐centrosymmetric spin‐switchable systems are of interest for their prospective applications as magnetically active non‐linear optical materials and in multiferroic devices. Chiral resolution of simple spin‐crossover chelate complexes into the Δ and Λ forms offers a facile route to homochiral magnetic switches, which could be easily enantiomerically enriched. Here, we report the spontaneous resolution of a new hysteretic spin‐crossover complex, [MnIII(sal2323)]SCN ⋅ EtOH (1), into Δ and Λ forms, without the use of chiral reagents, where sal2323 is a Schiff base resulting from condensation of 1,2‐bis(3‐aminopropylamino)ethane with 2‐hydroxybenzaldehyde. The enantiopurity of the Δ and Λ isomers was confirmed by single crystal X‐ray diffraction and circular dichroism. Quantum chemistry calculations were used to investigate the electronic structure. The opening of a wide 80 K thermal hysteresis window at high temperature highlights the potential for good magneto‐optical function at ambient temperature for materials of this type.