A Photoreactor-Interfaced Mass Spectrometer: An Online Platform to Monitor Photochemical Reactions.

Area of Science:

• Analytical Chemistry
• Photochemistry
• Chemical Engineering

Background:

• Characterizing photochemical reactions often requires offline analysis, which can be time-consuming and may miss transient intermediates.
• Developing integrated systems for online monitoring of photoreactions is crucial for efficient reaction optimization and mechanistic elucidation.

Purpose of the Study:

• To report a novel experimental platform for the online characterization of photochemical reactions.
• To demonstrate the platform's capability in analyzing diverse photoreactions in real-time.

Main Methods:

• Coupling a continuous flow photoreactor with LED irradiation and a dual-electrospray ionization (ESI) source directly to a mass spectrometer.
• Utilizing electrospray ionization mass spectrometry (ESI-MS) for online detection and analysis.
• Applying the platform to study photopolymerization and photocatalyzed alkyne insertion reactions.

Main Results:

• The integrated system successfully performed online characterization of methyl methacrylate photopolymerization.
• The platform effectively monitored photocatalyzed alkyne insertion into 1,2,3-benzotriazinone.
• Real-time data acquisition provided rapid insights into reaction mechanisms and overall photochemistry.

Conclusions:

• The developed online platform offers a powerful tool for rapid and comprehensive characterization of photochemical reactions.
• This integrated approach accelerates the understanding of photochemical processes and facilitates reaction optimization.
• The system's versatility is demonstrated across different classes of photoreactions.