Synthesis of (−)-trachelanthamidine using a single electron transfer reaction in 1,4-dimethylpiperazine

Synthesis of (−)-trachelanthamidine, one of the pyrrolizidine alkaloids, has been achieved by using a single electron transfer reaction of 2-(2-acetoxyethenyl)-N-(trichloroacetyl)pyrrolidine in boiling 1,4-dimethylpiperazine as the key step.