Tilting a ground-state reactivity landscape by vibrational strong coupling

Area of Science:

• Chemical Physics
• Organic Chemistry
• Physical Chemistry

Background:

• Traditional chemical methods often struggle with site selectivity in complex molecules.
• Controlling reactivity at specific sites is crucial for efficient synthesis.
• Novel approaches are needed to overcome limitations in traditional synthetic methods.

Purpose of the Study:

• To investigate the use of vibrational strong coupling (VSC) as a tool for achieving site selectivity in chemical reactions.
• To explore how VSC influences the reactivity of molecules with multiple potential reaction sites.
• To demonstrate control over product distribution by manipulating molecular vibrations.

Main Methods:

• Utilized a microfluidic optical cavity to achieve VSC between a reactant and the vacuum field.
• Studied the reactivity of a model compound with two distinct silyl bond cleavage sites (Si-C and Si-O).
• Applied VSC to three specific vibrational modes of the reactant in the dark.

Main Results:

• Demonstrated that VSC can selectively alter the reaction pathway, favoring one product over the other.
• Observed significant changes in thermodynamic parameters, including activation barrier and activation entropy.
• Confirmed a modification of the chemical landscape under strong coupling conditions.

Conclusions:

• Vibrational strong coupling offers a new paradigm for controlling chemical reactivity and site selectivity.
• The ability to tune reaction outcomes via VSC opens possibilities for designing novel synthetic strategies.
• This work highlights the potential of light-matter interactions to influence chemical transformations.