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