An asymmetric catalytic decarboxylative [4+2] annulation of 4‐ethynyl dihydrobenzooxazinones and carboxylic acids has been established by cooperative copper and nucleophilic Lewis base catalysis. A C1 ammonium enolate and copper–allenylidene compl...
An asymmetric catalytic decarboxylative [4+2] annulation of 4‐ethynyl dihydrobenzooxazinones and carboxylic acids has been established by cooperative copper and nucleophilic Lewis base catalysis. A C1 ammonium enolate and copper–allenylidene complex, each catalytically generated from different substrates, underwent a cascade asymmetric propargylation and lactamization process to yield optically active 3,4‐dihydroquinolin‐2‐one derivatives with excellent levels of stereoselectivity (up to 99 % ee, 95:5 d.r.).
Teamarbeit: C1‐Ammoniumenolate und Kupferallenylidene für die Titelreaktion werden katalytisch aus Carbonsäuren bzw. 4‐Ethinyldihydrobenzoxazinonen erzeugt. Die 3,4‐Dihydroquinolin‐2‐on‐Produkte werden hoch stereoselektiv gebildet.