Novel total syntheses of (±)-oxerine by intramolecular Heck reaction

Both a three-step and a five-step syntheses of monoterpene alkaloid (±)-oxerine from alcohol have been accomplished. In the second approach, the synthetic efficiency was enhanced by implementing a one-pot protocol (deprotonation/silylation/ alkylation/desilylation). The construction of the cyclopenta[c]pyridine framework was realized by an intramolecular Heck reaction, which should be adaptable for the synthesis of other related monoterpene pyridine alkaloids.