Conflicting Aromaticity in Trirhodium(I) Rosarin

Area of Science:

• Organic Chemistry
• Inorganic Chemistry
• Theoretical Chemistry

Background:

• Aromaticity is a fundamental concept in chemistry.
• Conflicting aromaticity, a state of simultaneous aromatic and antiaromatic electron delocalization, has been theoretically predicted but remains elusive.
• Understanding conflicting aromaticity is crucial for advancing chemical principles.

Purpose of the Study:

• To synthesize and characterize a novel molecule exhibiting conflicting aromaticity.
• To experimentally validate the theoretical predictions of conflicting aromaticity.
• To expand the known family of aromatic compounds.

Main Methods:

• Synthesis of a novel trirhodium complex.
• Characterization using nuclear magnetic resonance (NMR) spectroscopy.
• High-resolution mass spectrometry (HRMS) and X-ray single crystal structure analysis.
• Quantum chemical calculations.

Main Results:

• Successful synthesis of a trirhodium complex with conflicting aromaticity.
• Experimental confirmation of simultaneous σ-aromaticity in the metal fragment and π-antiaromaticity in the organic ligand.
• Validation of quantum chemical calculations with experimental data.

Conclusions:

• The synthesized trirhodium complex demonstrates unique conflicting aromaticity.
• This work provides the first experimental evidence of conflicting aromaticity in a synthesized molecule.
• The discovery opens new avenues for research into aromaticity and its diverse phenomena.