Homogeneous heterogeneous catalysis in CuO-nanoparticle-catalyzed C-C coupling reactions

• Published in: Green chemistry : an international journal and green chemistry resource : GC Vol. 21; no. 19; pp. 5284 - 529
• Main Authors: Addanki Tirumala, Ravi Teja, Dadgar, Andishaeh, Mohammadparast, Farshid, Ramakrishnan, Sundaram Bhardwaj, Mou, Tong, Wang, Bin, Andiappan, Marimuthu
• Format: Journal Article
• Published: 30.09.2019
• ISSN: 1463-9262; 1463-9270
• DOI: 10.1039/c9gc01930h

Copper based nanocatalysts have recently emerged as attractive catalysts for a diversity of bond formations, such as C-C, C-N, C-O, C-S, and C-Se. However, the identification of truly heterogeneous versus homogeneous catalytic conditions remains an ongoing challenge within the field. Herein, we report that in cuprous oxide (Cu 2 O) nanoparticle-mediated C-C homo-coupling and cross-coupling reactions, the presence of a base facilitates the copper complex mediated homogeneous catalytic pathway. Whereas in the absence of a base, the reaction can proceed heterogeneously on the surface of Cu 2 O nanoparticles. We distinguished the homogenous versus heterogeneous pathways using a combination of reactor study, ultraviolet-visible extinction spectroscopy, electrospray ionization mass spectrometry, flame atomic absorption spectroscopy, transmission electron microscopy, and density-functional theory calculations. Our findings indicate that Cu 2 O nanoparticles can catalyze C-C coupling reactions under lingandless and base-free conditions via a truly heterogeneous pathway paving the way for the development of highly efficient, robust and sustainable processes. Copper based nanocatalysts have recently emerged as attractive catalysts for a diversity of bond formations, such as C-C, C-N, C-O, C-S, and C-Se.