σ-Hole···π and lone pair···π interactions in benzylic halides

Area of Science:

• Organic Chemistry
• Supramolecular Chemistry
• Computational Chemistry

Background:

• Halogen bonding is a significant non-covalent interaction.
• Understanding halogen···π interactions is crucial for designing novel molecular architectures.
• The 7-phenylnorbornane framework imposes specific geometric constraints.

Purpose of the Study:

• To investigate intermolecular and intramolecular halogen···π interactions in benzylic halides.
• To elucidate the role of the 7-phenylnorbornane moiety in directing these interactions.
• To characterize the nature and impact of these interactions on molecular stability and electronic structure.

Main Methods:

• X-ray crystallography for solid-state analysis.
• UV-Vis spectroscopy and deuterium Nuclear Magnetic Resonance (D-NMR) for solution-state studies.
• Density Functional Theory (DFT) calculations for computational analysis.

Main Results:

• Crystallographic data confirmed intermolecular halogen bonds in specific iodide and bromide compounds.
• Solution-state data (UV-Vis, D-NMR) indicated intramolecular interactions between halogens and phenyl rings.
• DFT calculations verified the presence of lone pair···π intramolecular interactions.

Conclusions:

• The 7-phenylnorbornane structure inhibits intramolecular halogen···π interactions in the solid state.
• Intramolecular lone pair···π interactions are present in solution, influencing stability.
• These findings contribute to understanding non-covalent interactions in organic molecules.