Synthesis of heterocyclic compounds by radical electrochemical approach in environmentally friendly media

• Autor(a) principal: Duñach, E.
• Data de Publicação: 2008
• Outros Autores: Esteves, Ana Paula, Neves, C. S. S., Medeiros, Maria José
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/1822/25658

Radical cyclisation is rapidly becoming an important method for the formation of cyclic systems. Hence, some electrochemical results obtained in the study of electroreductive intramolecular cyclisation of ethyl 2-bromo-3-(3,4-methylenedioxophenyl)-3-(propargyloxy)propanoate (1a), [1-bromo-2-methoxy-2-(prop-2’-ynyloxy) ethyl] benzene (1b) and 1-[2-bromo-2-phenyl-1-(prop-2’-ynyloxy)ethyl]-4-methoxybenzene (1c) promoted by (1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetra-decane)nickel(I), [Ni(tmc)]+, electrogenerated at glassy carbon cathodes in ethanol, ethanol / water and microemulsions made with cationic and anionic surfactants are presented. The results obtained indicate that the reaction proceeds via cleavage of the carbon–bromine bond to form a radical intermediate that undergoes cyclization on the unsaturated C-C bond to afford the substituted tetrahydrofurans.