Supramolecular iron metallocubanes exhibiting site-selective thermal and light-induced spin-crossover - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Journal of the American Chemical Society Année : 2019

Supramolecular iron metallocubanes exhibiting site-selective thermal and light-induced spin-crossover

Résumé

Treatment of Fe[BF4]2·6H2O with 4,6-di(pyrazol-1-yl)-1H-pyrimid-2-one (HL1) or 4,6-di(4-methylpyrazol-1-yl)-1H-pyrimid-2-one (HL2) affords solvated crystals of [{FeIII(OH2)6}⊂FeII8(μ-L)12][BF4]7 (1, HL = HL1; 2, HL = HL2). The centrosymmetric complexes contain a cubic arrangement of iron(II) centers, with bis-bidentate [L]− ligands bridging the edges of the cube. The encapsulated [Fe(OH2)6]3+ moiety templates the assembly through 12 O–H···O hydrogen bonds to the [L]− hydroxylate groups. All four unique iron(II) ions in the cages are crystallographically high-spin at 250 K, but they undergo a gradual high → low spin-crossover on cooling, which is predominantly centered on one iron(II) site and its symmetry-related congener. This was confirmed by magnetic susceptibility data, light-induced excited spin state trapping (LIESST) effect measurements, and, for 1, Mössbauer spectroscopy and diffuse reflectance data. The clusters are stable in MeCN solution, and 1 remains high-spin above 240 K in that solvent. The cubane assembly was not obtained from reactions using other iron(II) salts or 4,6-di(pyrazol-1-yl)pyrimidine ligands, highlighting the importance of hydrogen bonding in templating the cubane assembly.

Domaines

Matériaux
Fichier principal
Vignette du fichier
2019-150.pdf (1.69 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Commentaire : Principe de précaution - Embargo de 12 mois préconisé par l'éditeur
Loading...

Dates et versions

hal-02383213 , version 1 (02-07-2020)

Identifiants

Citer

Izar Capel Berdiell, Tim Hochdörffer, Cédric Desplanches, Rafal Kulmaczewski, Namrah Shahid, et al.. Supramolecular iron metallocubanes exhibiting site-selective thermal and light-induced spin-crossover. Journal of the American Chemical Society, 2019, 141 (47), pp.18759-18770. ⟨10.1021/jacs.9b08862⟩. ⟨hal-02383213⟩
95 Consultations
38 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More