A Practical Preparation of the Indolizidine Nucleus: Synthesis of (+/-)-Elaeokanine A

Article abstract of DOI:10.1021/jo00003a064

Reduction of 3 followed by acid-catalyzed cyclization provides α,β-unsaturated ester 5.As 3 can be prepared in two steps from succinimide, acrolein, and trimethyl phosphonoacetate, this is a practical method for the assembly of the indolizidine nucleus.The structure of 5 was secured by conversion to elaeokanine A, 7.