Macrocyclic complexes of lead(II): crystal structures of LPb(ClO4)2 and LPb(NO3)2 (L = 1,4,7-triazacyclononane)

The reactivity of macrocyclic Fe(II) paraCEST MRI contrast agents towards biologically relevant anions, cations, oxygen or peroxide

“…The reduction potentials were 860 mV, 930 mV, 970 mV and 800 mV versus NHE, respectively. The reduction potential of [Fe(L3)] 2+ was similar to that reported previously [20]. …”

“…For example, the brown-red [Fe(L3)] 2+ possesses an intense MLCT band with a peak maximum at λ = 434 nm and a molar extinction coefficient ε = 1.0 × 10 4 M − 1 cm − 1 . These absorption properties of the complex in water are similar to those reported in acetonitrile solutions of [Fe(L3)] 2+ [20]. The high spin [Fe(L2)] 2+ complex has a corresponding peak that is tentatively assigned as a metal-to-ligand charge-transfer (MLCT) band at λ = 368 nm (ε = 1030 M − 1 cm − 1 ).…”

Two novel extended lead(II) coordination polymers generated from bridging Schiff-base ligands

“…SI-3). The Pb atoms are bonded by four O atoms of two nitrate anions with distances of Pb1Á Á ÁO4C = 3.043(6) Å , Pb1Á Á ÁO2D = 2.848(5) Å , Pb1Á Á ÁO2C = 3.173(5) Å and Pb1Á Á ÁO4D = 3.277(6) Å (symmetry code: (C) À1 + x, y, z; (D) 1 À x, 1 À y, 1 À z), these PbÁ Á ÁO bond lengths are in good agreement with corresponding bond lengths in the other complexes [22]. One N atom (N3D) of the hydrazinic group of Hpcih ligand point to the same Pb 2+ ion center with the distance of Pb1Á Á ÁN3D = 3.117(6) Å , shorter than the sum of the van der Waals' radii (3.54 Å ).…”

Two new lead(II) coordination polymer and discrete complex containing bipyridine ligands with different positioned methyl substituents: synthesis, characterization, crystal structure determination, and luminescent properties

“…The non-covalent OÁÁÁO interactions are well-established in the literature including their theoretical aspects. This type of interactions is also known to be responsible for the sulfate anion helices [59].…”