Synthesis of benzoazocines from substituted tetrahydroisoquinolines and activated alkynes in a tetrahydropyridine ring expansion

Tetrahydroisoquinolines underwent tandem piperidine ring enlargement in the presence of activated alkynes in acetonitrile or methanol, producing tetrahydrobenzo[d]azocines in high yields. © Wiley-VCH Verlag GmbH & Co. KGaA, 2007.