Metal-centred planar [15]annulenes.

Area of Science:

• Organometallic Chemistry
• Materials Science
• Coordination Chemistry

Background:

• Ferrocene discovery marked modern organometallic chemistry.
• Out-of-plane annulene metal complexes are well-established.
• In-plane annulene metal complexes are synthetically challenging.

Purpose of the Study:

• To prepare metal-centered planar [15]annulene frameworks.
• To investigate the electronic and structural properties of these novel complexes.
• To explore their potential as building blocks in materials science.

Main Methods:

• Synthesis of three metal-centered planar [15]annulene frameworks.
• Characterization using spectroscopic methods.
• Density functional theory (DFT) calculations to analyze electronic structure and aromaticity.

Main Results:

• Successfully prepared three metal-centered planar [15]annulene frameworks.
• The most symmetrical framework exhibits D5h symmetry.
• DFT calculations confirmed metal d orbital participation in conjugation, leading to aromaticity.
• The frameworks show stability and are easily functionalized.

Conclusions:

• The study reports the first isolation of metal-centered planar annulene frameworks.
• These systems bridge annulene chemistry and heteroatom coordination chemistry.
• Metal-centered planar annulenes are promising building blocks for advanced materials.