A versatile dinucleating ligand containing sulfonamide groups.

Area of Science:

• Coordination Chemistry
• Inorganic Chemistry
• Supramolecular Chemistry

Background:

• The development of novel ligands is crucial for advancing coordination chemistry.
• Pentadentate ligands offer unique coordination environments for metal ions.
• Bis-sulfonamide ligands present versatile coordination modes.

Purpose of the Study:

• To investigate the coordination chemistry of copper, iron, and gallium with a new pentadentate bis-sulfonamide ligand, psmpH3.
• To explore the structural diversity and magnetic properties of the resulting metal complexes.
• To understand the influence of ligand deprotonation on complex formation.

Main Methods:

• Synthesis and characterization of metal complexes.
• X-ray crystallography for structural determination.
• Magnetic susceptibility measurements.
• Computational studies using density functional theory (DFT).

Main Results:

• Formation of diverse complexes with varying ligand/metal stoichiometries (1:2, 2:3, 2:1).
• Observation of novel coordination modes, including μ2-N-sulfonamido bridging.
• Demonstration of flexible dimetallic binding sites with varying Cu···Cu distances.
• Characterization of strong and medium antiferromagnetic coupling in dicopper(II) complexes (J = 234 cm⁻¹, 115 cm⁻¹).
• Computational validation of antiferromagnetic coupling in a trinuclear copper complex (J = 70.5 cm⁻¹).

Conclusions:

• The pentadentate bis-sulfonamide ligand (psmpH3) effectively coordinates with Cu(II), Fe(III), and Ga(III) ions.
• Ligand deprotonation allows for the formation of complexes in aqueous solutions with divalent metal ions.
• The complexes exhibit diverse structures and significant magnetic coupling interactions.
• The study provides insights into the fundamental coordination chemistry and magnetic behavior of these novel complexes.