Tandem Synthesis of Polysubstituted Pyridines via the Indium(III)-Triflate- Catalyzed Cycloaddition/Oxidative Aromatization of Blaise Reaction Intermediates with α,β-Unsaturated Ketones

摘要

A tandem one-pot method for the construction of polysubstituted pyridines with complete control of the substitution pattern has been developed. The zinc bromide β-enamino ester intermediates of the Blaise reaction of simple ni-triles with a Reformatsky reagent undergo Michael addition with conjugated ketones in the presence of a catalytic amount of In(OTf)3. Final intramolecular cyc-lization and oxidative aromatization yields polysubstituted pyridines in this tandem one-pot cascade.