A microfluidic photoreactor enables 2-methylbenzophenone light-driven reactions with superior performance.

Area of Science:

• Organic Chemistry
• Photochemistry
• Chemical Engineering

Background:

• 2-methylbenzophenones (2-MBPs) are key intermediates in organic synthesis.
• Photochemical reactions often suffer from low yields and slow rates.
• Coumarin photo-dimerization is a common limitation in related syntheses.

Purpose of the Study:

• To improve the efficiency of light-driven reactions for 2-MBPs.
• To develop a novel method for converting coumarins into valuable chromanone derivatives.
• To overcome limitations associated with traditional photochemical methods.

Main Methods:

• Utilized a specifically designed microfluidic photoreactor (MFP).
• Investigated light-driven reactions of 2-methylbenzophenones.
• Explored the conversion of coumarins to 4-benzylated chromanones.

Main Results:

• Achieved significantly improved yields (up to >98%) and reaction rates (up to 0.240 mmol h-1) for 2-MBP reactions.
• Successfully converted coumarins into 4-benzylated chromanones with high yields (50-93%) and diastereoselectivity (>20:1 dr).
• Demonstrated the ability to bypass coumarin photo-dimerization.

Conclusions:

• Microfluidic photoreactors offer a superior platform for photochemical transformations.
• A novel synthetic route to 4-benzylated chromanones from coumarins has been established.
• This work provides efficient and selective methods for key organic transformations.