Silane Redistribution Catalyzed by [Mes-B-TMP]⁺ Borinium Ion

Area of Science:

• Organometallic Chemistry
• Catalysis
• Boron Chemistry

Background:

• Borinium ions are potent Lewis acids due to empty p orbitals on boron.
• Their high reactivity often hinders practical applications in catalysis.
• Developing stable yet active borinium ion catalysts is crucial for synthetic chemistry.

Purpose of the Study:

• To synthesize and characterize a novel arylamino borinium ion catalyst.
• To investigate its efficacy in mediating aryl transfer reactions.
• To explore its potential for activating silicon-based substrates.

Main Methods:

• Synthesis of the arylamino borinium ion [1]+.
• Catalytic aryl transfer reactions using ArMe2SiH as the aryl source.
• Cross-coupling reactions with various hydrosilanes.
• Density functional theory (DFT) calculations to elucidate the reaction mechanism.

Main Results:

• The arylamino borinium ion [1]+ efficiently catalyzed aryl transfer from ArMe2SiH to afford Ar2SiMe2 and Me2SiH2 under mild conditions.
• The catalyst enabled cross-coupling reactions between different hydrosilanes.
• Computational studies confirmed the role of the amino group in modulating Lewis acidity and preventing catalyst decomposition.

Conclusions:

• Electronically tuned borinium ions, like [1]+, can serve as effective catalysts for challenging organic transformations.
• The amino substituent is key to balancing Lewis acidity for reversible Si-H activation and catalyst stability.
• This work opens avenues for utilizing borinium ions in the activation of inert substrates.