Copper-supported thiol-functionalized cellulose as a paper-based catalyst for imine synthesis.

Area of Science:

• Green Chemistry
• Materials Science
• Catalysis

Background:

• Developing sustainable catalysts is crucial for environmentally friendly chemical synthesis.
• Cellulose-based materials offer a biodegradable and abundant platform for catalyst immobilization.
• Copper catalysts are widely used but often require efficient recovery and reuse strategies.

Purpose of the Study:

• To develop a novel, reusable catalyst using functionalized cellulose filter paper for copper-catalyzed reactions.
• To investigate the role of thiol functionalization in stabilizing active copper species.
• To demonstrate the catalyst's efficacy in the oxidative coupling of amines to imines.

Main Methods:

• Cellulose filter paper was functionalized with thiol groups using thioglycolic acid.
• Copper species (Cu(II)/Cu(I)) were loaded onto the functionalized paper.
• Spectroscopic techniques were used to characterize the catalyst's structure and copper species.
• The catalyst's performance was evaluated in the oxidative coupling of amines to imines.

Main Results:

• Thiol-functionalized cellulose successfully stabilized highly dispersed Cu2O/CuO nanoparticles.
• The paper-based copper catalyst exhibited excellent efficiency in amine-to-imine oxidative coupling, with yields ranging from 39-99%.
• The catalyst demonstrated high stability and reusability over ten reaction cycles with straightforward recovery.

Conclusions:

• Functionalized cellulose filter paper provides an effective and sustainable support for copper catalysts.
• This approach offers a cost-effective and eco-friendly alternative for synthetic processes.
• The reusable paper-based catalyst has significant potential for green chemistry applications and industrial implementation.