Regueiro-Figueroa, Martin published the artcileUnderstanding Stability Trends along the Lanthanide Series, Application of 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid, the publication is Chemistry – A European Journal (2014), 20(14), 3974-3981, database is CAplus and MEDLINE.
The stability trends across the lanthanide series of complexes with the polyaminocarboxylate ligands TETA4- (H4TETA = 2,2′,2”,2”’-(1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetrayl)tetraacetic acid), BCAED4- (H4BCAED = 2,2′,2”,2”’-{[(1,4-diazepane-1,4-diyl)bis(ethane-2,1-diyl)]bis(azanetriyl)}tetraacetic acid), and BP18C62- (H2BP18C6 = 6,6′-[(1,4,10,13-tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene)]dipicolinic acid) were investigated using DFT calculations Geometry optimizations performed at the TPSSh/6-31G(d,p) level, and using a 46 + 4fn ECP for lanthanides, provide bond lengths of the metal coordination environments in good agreement with the exptl. values observed in the X-ray structures. The contractions of the Ln3+ coordination spheres follow quadratic trends, as observed previously for different isostructural series of complexes. We show here that the parameters obtained from the quant. anal. of these data can be used to rationalize the observed stability trends across the 4f period. The stability trends along the lanthanide series were also evaluated by calculating the free energy for the reaction [La(L)]n+/-(sol) + Ln3+(sol)→[Ln(L)]n+/-(sol) + La3+(sol). A parameterization of the Ln3+ radii was performed by minimizing the differences between exptl. and calculated standard hydration free energies. The calculated stability trends are in good agreement with the exptl. stability constants, which increase markedly across the series for BCAED4- complexes, increase smoothly for the TETA4- analogs, and decrease in the case of BP18C62- complexes. The resulting stability trend is the result of a subtle balance between the increased binding energies of the ligand across the lanthanide series, which contribute to an increasing complex stability, and the increase in the absolute values of hydration energies along the 4f period.
Chemistry – A European Journal published new progress about 1128304-86-8. 1128304-86-8 belongs to pyridine-derivatives, auxiliary class Pyridines, name is 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid, and the molecular formula is C26H36N4O8, Application of 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid.
Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem