Submitted to: American Chemical Society Applied Nano Materials
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/19/2020
Publication Date: 6/19/2020
Citation: Easson, M.W., Jordan, J.H., Bland, J.M., Hinchliffe, D.J., Condon, B.D. 2020. Application of brown cotton-supported palladium nanoparticles in suzuki-miyaura cross-coupling reactions. American Chemical Society Applied Nano Materials. 3(7):6304-6309. https://doi.org/10.1021/acsanm.0c01303.
Interpretive Summary: The tannins within brown cotton are naturally occurring substances which allow for the deposition of gold and palladium nanoparticles within the fibers of the brown cotton fabric. Nanoparticles are structures that are a thousand times smaller than a human hair and are very useful in the preparation of pharmaceutical drugs. The palladium nanoparticles were applicable in carbon-carbon bond forming reactions, otherwise known as the Suzuki-Miyaura reaction. In the reaction two reactants were coupled together, forming a new product in yields ranging from 22% to >99%. Not only were these metal-treated fabrics useful in chemical reactions, they also proved to be quite durable, allowing for repeated use up to nine times. This new use for brown cotton has not been previously reported. This discovery opens up the possibility of forming nanoparticles with other metals and the possibility of discovering other reaction applications.
Technical Abstract: A simple method was found to deposit gold and palladium nanoparticles within the fibers of nonwoven brown cotton fabric (NBCF) using the naturally occurring polyphenolic tannins contained within the fibers. The prepared fabric retained Suzuki-Miyaura type catalytic activity for nine experimental repetitions, producing excellent yields without column chromatography. In a series of experiments to determine the scope of the application, product yields were affected by steric hindrance and aryl halide selection, with para-substituted and iodoaryl reactants providing the highest product yields. Catalytic loading was lowered to sub-milliequivalents levels in scaled reactions without loss of activity or yield. Deposition of palladium nanoparticles within cross-sections of cotton fiber was confirmed by scanning electron microscopy (SEM), inductively coupled photospectroscopy (ICP) and transmission electron microscopy (TEM). NBCF offers an inexpensive and sustainable substrate for metal nanoparticle inclusions.