Diphosphaindenyl π-complexes as a platform for hapticity-controlled metaloligand design

Area of Science:

• Organometallic Chemistry
• Coordination Chemistry
• Materials Science

Background:

• Phosphonium-substituted diphosphaindenyl (PPIAr) π-complexes offer tunable coordination modes.
• The indenyl effect influences the coordination behavior of metal carbonyl fragments.

Purpose of the Study:

• To investigate the coordination behavior of PPIAr π-complexes with 3d metal carbonyl fragments.
• To synthesize and characterize novel trimetallic complexes.
• To explore the electronic and geometric factors governing metal-ligand interactions.

Main Methods:

• Synthesis of trimetallic complexes involving chromium and iron.
• Characterization using spectroscopic and crystallographic techniques.
• Computational analysis including energy decomposition analysis (EDA).

Main Results:

• Formation of trimetallic complexes with gold and silver coinage metals.
• Iron-based metaloligands act as σ-donors.
• Chromium complex exhibits a unique η⁴, μ² bridging mode, enabling Cr-Ag covalent bonding.
• EDA reveals the interplay of non-orbital and geometric factors in dictating coordination.

Conclusions:

• PPIAr ligands facilitate diverse coordination modes in 3d metal complexes.
• The study presents a rare example of structurally characterized Cr-Ag bonding.
• Electronic and geometric factors are crucial for understanding metaloligand behavior.