An efficient synthesis of a highly functionalized 4-arylpiperidine

In this manuscript, an efficient synthesis of a functionalized 4-arylpiperidine is disclosed. Several synthetic approaches towards formation of the key aryl-piperidine sp3 carbon–carbon bond are discussed, including a scalable route to the piperidine via reaction of acyl pyridinium ions with aryl Grignard reagents to form the corresponding dihydropyridines. Methods to access the BOC protected piperidine through dihydropyridine intermediates are described.