Synthesis of constrained arylpiperidines using intramolecular Heck or radical reactions

Two intramolecular routes were experimented to reach the hexahydrobenzofuro[2,3-c]pyridine platform: a Heck and a radical reaction. The radical route was applicable to all substrates, whereas the Heck route was of limited use. The key adducts were obtained via a Mitsunobu condensation between halogenated phenols and an allylic alcohol, the 3-hydroxy-tetrahydropyridine.