Halogen bonds of halonium ions

Area of Science:

• Chemistry
• Supramolecular Chemistry
• Organic Chemistry

Background:

• Halonium ions are electron-deficient, making them potent halogen bond donors.
• They interact with two Lewis bases via their empty p-orbital, forming three-center interactions.
• These interactions are analogous to [D-H-D]+ hydrogen bonds, known for being short and strong.

Purpose of the Study:

• To explore the nature and properties of three-center halogen bonds in halonium ions.
• To highlight the distinct characteristics of these bonds compared to transition metal coordinative bonds.
• To provide an overview of current applications and stimulate future research.

Main Methods:

• The study reviews the electronic structure and bonding characteristics of halonium ions.
• It analyzes the properties of the resulting three-center halogen bonds, including interatomic distances and charge transfer.
• Comparative analysis with other bonding types is discussed.

Main Results:

• Halonium ions form [D-X-D]+ halogen bonds with normalized interatomic distances of 0.6-0.7.
• These bonds exhibit both charge transfer and electrostatic characteristics.
• The three-center halogen bond significantly modulates halonium ion reactivity.

Conclusions:

• Three-center halogen bonds in halonium ions are distinct from transition metal bonds and valuable in supramolecular chemistry.
• These bonds serve as complementary synthons, offering unique advantages.
• Understanding and utilizing these halogen bonds can advance synthetic organic chemistry.