Sulfonium cation [SF₃]⁺ complexes with noble gases

Area of Science:

• Inorganic chemistry
• Computational chemistry
• Supramolecular chemistry

Background:

• Chalconium cations are potent Lewis acids featuring hypervalent chalcogen atoms.
• They find applications in organocatalysis and crystal engineering.

Purpose of the Study:

• To investigate the electrophilic nature of chalconium cations.
• To model complexes of the [SF3]+ cation with noble gas atoms.

Main Methods:

• Computational modeling using a polarizable continuum model.
• Synthesis and characterization of [SF3(NCCH3)2Ng]+ and [SF3(Ng)2][SbF6] complexes (Ng = Ar, Kr, Xe).

Main Results:

• Stable tetrameric complexes with weak interaction energies (-2 to -1 kcal mol-1) were computed.
• Replacing the [SbF4]- anion or NCCH3 ligands with noble gas atoms weakened interaction energies.
• The nature of interaction shifted from electrostatic to dispersive upon noble gas substitution.

Conclusions:

• Noble gas atoms can act as ligands in chalconium cation complexes.
• The electronic environment significantly influences the bonding characteristics between chalconium cations and noble gases.