Spring‐Loaded Iron(II) Complexes as Magnetogenic Probes Reporting on a Chemical Analyte in Water

Abstract

International audienceA new low-spin iron(II) triazacyclononane-based complex, selected from four different candidates, acts as a molecular probe that turns a diamagnetic aqueous sample into a paramagnetic one as a response to a chemical analyte. The four complexes are prepared by a highly convergent synthetic protocol and give precious insights into structure–activity relationship (SAR) tendencies

Spin-crossover and high-spin iron(ii) complexes as chemical shift19F magnetic resonance thermometers

“…With the goal to prepare air- and water-stable complexes, tacn-based ligands bearing three pendent pyridyl groups offer an ideal platform, as these hexadentate scaffolds have been shown to afford highly-stable Fe II complexes. 10 , 21 In addition, the ligand field can be readily tuned to obtain spin-crossover complexes within a physiologically relevant temperature range by chemical modulation of the electronic and steric properties of the pyridyl donors. 21e , 22 Toward this end, we sought to synthesize related ligands that support Fe II complexes in selected spin states through controlled introduction of methyl groups into the 6-position of the pyridyl groups, which serves to weaken the ligand field by virtue of steric crowding at the Fe II center.…”

Molecular Sensors Operating by a Spin‐State Change in Solution: Application to Magnetic Resonance Imaging

“…Finally, our group has reported several systems that can switch from one spin state to another in an irreversible manner. [76,77,78] All are based on iron(II), and for the moment, all comprise the macrocycle TACN. [19,79] The intact sensors are thus of a binary nature and resist the competitive nature of aqueous media fairly well.…”

Imaging of copper oxygenation reactions in a bubble flow

“…This approach relates to magnetogenics, where chemical probes react to the chemical environment of molecules and change the relaxation parameters. They are most valuable in medicine . Moreover there are applications to visualizing chemical waves .…”

“…They are most valuable in medicine. [24][25][26] Moreover there are applications to visualizing chemical waves. [27] Here, an application to chemical engineering is presented.…”