Syntheses of 7a-Substituted Pyrrolizidine Derivatives via Stereocontrolled Anionic Cyclization

Abstract Starting from inexpensive proline and epichlorohydrin, a pivotal stereocontrolled anionic cyclization reaction paves the way for a robust and adaptable methodology to produce stereoisomers of 7a-substituted pyrrolizidine derivatives. This process yields intriguing 7a-hydroxymethyl pyrrolizidine derivatives, among them valuable trans-(2-fluorohexahydro-1H-pyrrolizin-7a-yl)methanol, which is attainable through multiple steps.