Au-Cavitands: Size governed arene-alkyne cycloisomerization

Area of Science:

• Organometallic Chemistry
• Supramolecular Chemistry
• Catalysis

Background:

• Gold(I) complexes are effective catalysts for various molecular transformations.
• Resorcinarene cavitands offer a unique structural framework with a binding pocket and inwardly directed reactive center.
• The constrained environment of cavitands can influence catalyst reactivity and selectivity.

Purpose of the Study:

• To investigate the catalytic activity of Au(I) functionalized resorcin[4]arene cavitands.
• To explore how substrate structure, specifically alkyne and aromatic composition and fit within the cavitand pocket, affects reaction outcomes.
• To understand the role of scaffold size in dictating reactivity and selectivity in cavitand-mediated catalysis.

Main Methods:

• Synthesis of Au(I) functionalized resorcin[4]arene cavitands.
• Intramolecular cyclization reactions of alkyne-aromatic substrates with varied compositions.
• Analysis of reaction outcomes based on substrate features and cavitand scaffold size.

Main Results:

• Au(I) cavitand catalysts exhibit distinct reactivity profiles compared to other Au(I) catalysts.
• Substrate fit within the resorcinarene binding pocket influences reaction outcomes.
• Scaffold size of the cavitand was identified as a critical factor dictating reactivity, particularly for specifically designed substrates.

Conclusions:

• Resorcinarene cavitands provide a tunable platform for selective gold catalysis.
• The spatial constraints imposed by the cavitand pocket significantly impact catalytic efficiency and selectivity.
• This work expands the understanding of structure-activity relationships in supramolecular catalysis, highlighting the potential of cavitands for designing bespoke catalysts.