Stereoselective Synthesis of the Eastern Quinolizidine Portion of Himeradine A

The synthesis of the C₁₅–C₁₇/N_1′–C_11′ quinolizidine portion of himeradine A is disclosed. An intramolecular, heteroatom Michael addition was employed to establish the C_6′ stereogenic center with high diastereoselectivity. The quinolizidine ring was constructed using microwave-induced cyclization at the N_1′–C_2′ position. The C₁₇ stereogenic center was introduced through a diastereoselective Overman rearrangement.