Shaffer, David W. published the artcileSpin-state diversity in a series of Co(II) PNP pincer bromide complexes, Quality Control of 338800-13-8, the publication is Dalton Transactions (2016), 45(44), 17910-17917, database is CAplus and MEDLINE.
The authors describe the structural and electronic impacts of modifying the bridging atom in a family of Co(II) pincer complexes Co(t-Bu)2PEPyEP(t-Bu)2Br2 (Py = pyridine, E = CH2, NH, and O for compounds 1–3, resp.). Structural characterization by single crystal x-ray diffraction indicates that compounds 1 and 3 are 5-coordinate complexes with both bromides bound to the Co ion, while compound 2 is square planar with one bromide in the outer coordination sphere. The reduction potentials of 1–3, characterized by cyclic voltammetry, are consistent with the increasing electron-withdrawing character of the pincer ligand as the linker (E) between the pyridine and phosphine arms becomes more electroneg. Magnetic property studies of compounds 1 and 2 confirm high- and low-spin behavior, resp., through a broad temperature range. However, complex 3 features an unusual combination of high spin S = 3/2 Co(II) and temperature dependent spin-crossover between S = 3/2 and S = 1/2 states. The different magnetic behaviors observed among the three CoBr2 pincer complexes reflects the importance of small ligand perturbations on overall coordination geometry and resulting spin state properties.
Dalton Transactions published new progress about 338800-13-8. 338800-13-8 belongs to pyridine-derivatives, auxiliary class Bis-phosphine Ligands, name is 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, and the molecular formula is C7H5ClN2S, Quality Control of 338800-13-8.
Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem