6533b861fe1ef96bd12c502f
RESEARCH PRODUCT
An Octanuclear Metallosupramolecular Cage Designed To Exhibit Spin-Crossover Behavior.
Tanya K. RonsonNorbert WagnerNiklas StruchRakesh PuttreddyChristoph BannwarthYvonne LorenzKari RissanenArne LützenJonathan R. NitschkeBernd MienertStefan GrimmeMarianne EngeserJohannes BeckEckhard Billsubject
Stereochemistrychemistry.chemical_elementZinc010402 general chemistryMass spectrometry01 natural sciencesCatalysislaw.inventionhost-guest systemschemistry.chemical_compoundspin crossoverlawSpin crossoverMössbauer spectroscopySpectroscopyta116010405 organic chemistryChemistryiron(II) complexesGeneral Chemistryself-assemblymetallosupramolecular chemistryPorphyrinSynchrotron0104 chemical sciencesCrystallographyDiamagnetismdescription
By employing the subcomponent self-assembly approach utilizing 5,10,15,20-tetrakis(4-aminophenyl)porphyrin or its zinc(II) complex, 1H-4-imidazolecarbaldehyde, and either zinc(II) or iron(II) salts, we were able to prepare O-symmetric cages having a confined volume of ca. 1300 Å3 . The use of iron(II) salts yielded coordination cages in the high-spin state at room temperature, manifesting spin-crossover in solution at low temperatures, whereas corresponding zinc(II) salts led to the corresponding diamagnetic analogues. The new cages were characterized by synchrotron X-ray crystallography, high-resolution mass spectrometry, and NMR, Mössbauer, IR, and UV/Vis spectroscopy. The cage structures and UV/Vis spectra were independently confirmed by state-of-the-art DFT calculations. A remarkably high-spin-stabilizing effect through encapsulation of C70 was observed. The spin-transition temperature T1/2 is lowered by 20 K in the host-guest complex.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2018-03-29 |