Efficient Synthesis of Amino Lactones via Copper-catalysed Alkene Aminooxygenation

Abstract

The synthesis of 5–7 membered oxygenated heterocycles by intramolecular aminooxygenation of unsaturated alkenes using commercially available N-fluorobenzenesulfonimide as amination reagent and TpiPr2Cu(NCCH3) as precatalyst is reported. With unsaturated aliphatic carboxylic acids, the corresponding lactones are obtained from moderate to almost quantitative yields employing a catalyst loading of 2.5 mol% under mild conditions, whereas 2-vinylbenzoic acids originate lower yields.