Divergent Pd-catalyzed and radical cyclizations of nucleophilic cyclic enamines derived from functionalized amine and aldehyde fragments.
Tetrahydropyridines carrying pendant halide functionality at the enamine beta-carbon have been prepared by condensation between appropriately functionalized aldehydes and a vinylogous Mannich adduct. Those enamines display divergent behavior in radical and Heck reactions. Thus, radical addition takes place in a 5-exo-trig fashion whereas Heck couplings follow a 6-endo-trig pathway. The resulting polycyclic products are obtained with high regio- and stereoselectivity.
Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, 48080 Bilbao, Spain. jm.aurrecoechea@ehu.es
José M
JM
Aurrecoechea
Carlos A
CA
Coy
Oscar J
OJ
Patiño