Dearomatization of N-Phenyl-2,6-dialkylpiperidines: Practical Synthesis of (±)-Solenopsin A and (±)-Dihydropinidine

The fire ant venom alkaloid (±)-solenopsin A was prepared in 4 steps (34%) starting from the N-phenyl-2-undecyl piperidine (1c). The key step in this synthesis involved the dearomatization of the phenyl group of N-phenyl-2-methyl-6-undecyl-piperidine (9c), which was carried out under Birch conditions.