A continuous-flow protocol for photoredox-catalyzed multicomponent Petasis reaction.

Area of Science:

• Organic Chemistry
• Flow Chemistry
• Photocatalysis

Background:

• Secondary amines are crucial building blocks in pharmaceuticals and organic synthesis.
• Traditional synthesis methods can be time-consuming and lack scalability.
• Continuous flow chemistry offers advantages in reaction control and efficiency.

Purpose of the Study:

• To develop a rapid and robust protocol for synthesizing functionalized secondary amines.
• To demonstrate the utility of a photocatalyzed Petasis reaction in a continuous flow system.
• To establish a scalable method for amine synthesis using readily available precursors.

Main Methods:

• Utilized a Vapourtec E-series continuous flow reactor.
• Employed a photocatalyzed Petasis reaction with alkyl boronic acids as radical precursors.
• Optimized reaction conditions for rapid synthesis within 50 minutes.

Main Results:

• Successfully synthesized functionalized secondary amines in mmol scale.
• Achieved a high productivity rate of 0.2 mmol/h.
• Demonstrated the protocol's effectiveness for alkyl boronic acids.

Conclusions:

• The developed continuous flow protocol provides a facile and rapid method for secondary amine synthesis.
• This approach offers an efficient alternative to traditional batch synthesis for specific amine targets.
• The protocol is suitable for producing functionalized amines from alkyl boronic acids.