Aromaticity Tuning in Biaryl Monophosphines and Their Derivatives

Area of Science:

• Organic Chemistry
• Catalysis
• Computational Chemistry

Background:

• Biaryl monophosphines are vital ligand precursors for asymmetric catalysis.
• Tuning their aromaticity influences catalytic efficiency.

Purpose of the Study:

• Investigate aromaticity tuning in biaryl monophosphine derivatives.
• Correlate aromaticity with steric and electronic properties for catalyst design.

Main Methods:

• X-ray diffraction (XRD) and Hirshfeld surface analysis.
• Density Functional Theory (DFT) calculations for aromaticity indices (HOMA, HOMER, NICS).

Main Results:

• NICS(1)zz proved most sensitive to aromaticity changes.
• Methoxy substituents improved performance over hydroxy groups.
• Hydroxy groups caused unfavorable hydrogen bonding and blocked phosphorus atom access.

Conclusions:

• Subtle changes in biaryl monophosphine scaffolds, particularly aromaticity, are critical for rational catalyst design.
• Optimized ligands promote C,P-chelated palladacyclic structures for efficient Pd-C bond formation.