New Cd2+, Pb2+ complexes with acylhydrazidate molecules from in situ acylation reactions

Area of Science:

• Coordination Chemistry
• Materials Science
• Supramolecular Chemistry

Background:

• Acylhydrazidate ligands are versatile building blocks in coordination chemistry.
• Hydrothermal synthesis offers a controlled environment for complex formation.
• Understanding structure-property relationships in metal complexes is crucial for materials design.

Purpose of the Study:

• To synthesize and characterize novel acylhydrazidate-coordinated metal complexes.
• To investigate the structural diversity and supramolecular assembly of these complexes.
• To explore their luminescent properties in different states.

Main Methods:

• Hydrothermal in situ acylation of hydrazine with aromatic dicarboxylic acids.
• Single-crystal X-ray diffraction for structural analysis.
• Luminescence spectroscopy and Density Functional Theory (DFT) calculations.

Main Results:

• Four new cadmium and lead complexes with phthalhydrazidate, dichlorophthalhydrazidate, pyridine-dicarboxylhydrazidate, and sulfoyldiphthalhydrazidate ligands were obtained.
• Complexes exhibit diverse structural motifs, including 1-D double and single chains, and self-assemble into 2-D supramolecular networks via hydrogen bonding.
• Luminescence was observed in the solid state for complex 3 and in aqueous solution for complexes 1, 3, and 4, with DFT confirming charge transfer origins.

Conclusions:

• The hydrothermal acylation method is effective for synthesizing novel acylhydrazidate-metal complexes.
• The coordination modes of ligands and hydrogen bonding play key roles in the formation of intricate 1-D and 2-D supramolecular architectures.
• The luminescent properties are dependent on the complex structure and the medium, with potential applications in sensing or light-emitting devices.