Synthesis of Spirodienones by Intramolecular Ipso-Cyclization of <i>N</i>-Methoxy-(4-halogenophenyl)amides Using [Hydroxy(tosyloxy)iodo]benzene in Trifluoroethanol

Abstract

Spirodienones bearing the 1-azaspiro[4.5]decane ring system have been synthesized from N-methoxy-(4-halogenophenyl)amides by the intramolecular ipso attack of a nitrenium ion generated with [hydroxy(tosyloxy)iodo]benzene in trifluoroethanol.