Synthesis and characterization of a series of acylpyrazolone transition metal complexes: Crystal structures and catalytic performance in the epoxidation of cyclooctene

Syntheses and Characterization of Main Group, Transition Metal, Lanthanide, and Actinide Complexes of Bidentate Acylpyrazolone Ligands

“…Crystallographic analysis revealed that the nickel­(II) complexes were of slightly distorted octahedral coordination with the two pyrazolonato ligands in a trans -arrangement, Table . The reported values correspond reasonably well to reported data with structures, which have been shown to display Ni–O bond lengths of 1.9966(12)–2.0442(17) Å, while the solvent ligands were reported with bond distances to the Ni­(II) center of 2.0651(16)–2.042(12) Å …”

“…X-Ray crystal structures of the Cu- or Zn-complexes 49 , 54 , and 55 were found to be polymeric in nature. Ni-pyrazolonato complexes have previously been reported with axial DMF, MeOH, or EtOH ligands …”

“…Complex 58 is octahedral with the two pyrazolonato ligands in a cis -arrangement, Figure . The structures of related compounds display Ni–O bond lengths of 1.9966(12)–2.0442(17) Å, while the solvent ligands were reported with bond distances to the Ni­(II) center of 2.0651(16)–2.042(12) Å …”

Distorted octahedral cobalt(ii)–acylpyrazolone complex with a tunable lattice-strain structure – an efficient electrocatalyst for overall water splitting

“…Nevertheless, pyrazolone Schiff base ligands and their complexes have received particular attention since the 1950s, 1 and their application was limited in the fields of biology, 6,7 metal ion extraction [1][2][3] and catalysis. 8,23 As per our knowledge and understanding, there has been no direct report on the use of cobalt-pyrazolone Schiff base complexes as homogeneous/heterogeneous electrocatalysts for electrochemical water splitting. Accordingly, in this work, acylpyrazolone ligands (HPMBP and HPMTP) and their corresponding cobalt complexes, aqua-1-phenyl-3-methyl-4benzoylpyrazolonecobalt(II), [Co(OH 2 ) 2 (PMBP) 2 ] (1), and aqua-1phenyl-3-methyl-4-toluoylpyrazolonecobalt(II), [Co(OH 2 ) 2 (PMTP) 2 ] (2), are synthesized and explored as electrocatalysts for water splitting reactions for the first time.…”

“…Nevertheless, pyrazolone Schiff base ligands and their complexes have received particular attention since the 1950s, 1 and their application was limited in the fields of biology, 6,7 metal ion extraction 1–3 and catalysis. 8,23…”