A convenient domino synthetic approach for the construction of the indolizidine core
in diastereoselective manner has been developed from inexpensive starting compounds,
providing triple functionalization. The novel synthetic route started from β-lactam
derived from 1,5-cyclooctadiene including a ring-opening metathesis/cross-metathesis
sequence as key steps with methyl acrylate followed by intramolecular ring closure
across an aza-Michael addition. The process gave functionalized indolizidine framework
with stereocontrol in high yields. DFT calculations supported the experimentally observed
stereoselective reaction.
Key words
azaheterocycles - indolizidine - metathesis - ring closure - stereocontrol