An asymmetric approach to the pyrrolizidine ring system via N-acetyl and N-propionyl anion cyclisation processes

Article abstract of DOI:10.1016/0040-4039(94)02233-2

An efficient route to the pyrrolizidine ring system has been developed. The method, which uses N-acetyl and N-propionyl anion cyclisation reactions as the key steps has provided the natural pyrrolizidines (-)-(1R, 8S)-1-hydroxypyrrolizidine (10), (-)-pyrrolizidin-1-ene-3-one (13), (±)-trachelanthamidine (18) together with a range of 2-methyl substituted pyrrolizidine-3-ones.