Regioselective generation of iminium cation by PET processes: its in situ trapping by intramolecular nucleophiles and synthesis of some biologically active heterocycles

摘要: Abstract Efficient, mild and direct route for regiospecific iminium cation is developed by sequential two electron oxidation of several N-alkylated tertiary amines photoinduced transfer processes. The regiospecificity arises from the deprotonation step amine radical to generate α-amino which depends on stereoelectronic factor subject kinetic acidity cation. Iminium efficiently trapped insitu internal nuleophiles give cyclic compounds 14–18 22a–c. Stereoselective synthesis cis α,α′-dialkylated piperidines pyrrolidines 30a–c achieved nucleophilic opening tetrahydro-1,3-oxazines