94-88-2Relevant academic research and scientific papers
Intramolecular Quenching of Iminium Ions Generated by Photooxidation of Aminoalcohols with Ketones. A New Synthesis of Oxazines and Oxazoles
Cossy, Janine,Guha, Madhumita
, p. 1715 - 1718 (2007/10/02)
The irradiation of tertiary amines in the presence of ketones leads to a regioselective and stereoselective formation of iminium salts which then react to afford the corresponding oxazines or oxazoles. - Key words : Ammoniumyl ions, iminium ions, electron transfer, amines, ketones, tetrahydrooxazine tetrahydrooxazoles.
Regioselective generation of iminium cation by PET processes: Its in situ trapping by intramolecular nucleophiles and synthesis of some biologically active heterocycles
Pandey,Kumaraswamy,Yella Reddy
, p. 8295 - 8308 (2007/10/02)
Efficient, mild and direct route for regiospecific iminium cation is developed by sequential two electron oxidation of several N-alkylated tertiary amines by photoinduced electron transfer processes. The regiospecificity of iminium cation arises from the deprotonation step of amine radical cation to generate α-amino radical which depends on the stereoelectronic factor subject to kinetic acidity of amine radical cation. Iminium cation is efficiently trapped in situ by internal nucleophiles to give cyclic compounds 14-18 and 22a-c. Stereoselective synthesis of cis α,α'-dialkylated piperidines and pyrrolidines 30a-c is achieved by nucleophilic opening of tetrahydro-1,3-oxazines 22a-c.
