Well defined copper(I) catalysts for the chemoselective oxidation reaction of alcohols to aldehydes

• Autor(a) principal: Machado, Beatriz Pereira
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/162946
• topic: DAB; DAD; BIAN; copper(I); benzylic alcohol; allylic alcohol; Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Química

One of the key concerns in contemporary chemistry is the development of sustainable processes that adhere as closely as possible to the principles of Green Chemistry without com- promising the activity of involved processes. Several principles can be applied in the develop- ment of this work, including the catalysis and the atomic economy, among others. The harsh conditions and the disposal of subproducts that characterize typical oxidation reactions pose significant challenges for the chemoselective oxidation of alcohols to benzaldehydes. To tackle these issues, the use of copper(I) complexes comprising diimine ligands, usually bipyridine and phenanthroline shown promising outcomes. Furthermore, new studies by our research group, suggests that bis-aryldiiminoacenaphthene ligands may also be effective, and even in- crease catalyst activity of such systems. However, such complexes regularly incorporate halo- gens as counterions. The impact of the diimine backbone on the catalytic activity and stability was investigated in the newly synthesised compounds. Additionally, the effects of the coun- terion and chelating solvent on the activity and stability were examined. Characterization of all compounds included mono and heteronuclear 1D and 2D-NMR, IR, EA, UV/Vis, and, when possible, X-ray diffraction. The efficiency of all compounds was tested in the oxidation reaction, and they all revealed to be active. Various conditions of the catalytic system were studied to optimize it, and subsequently, the catalytic system was tested with benzyl, allylic, and aliphatic alcohols for efficiency.