Efficient Synthesis of (2S,12′R)-2-(12′-Aminotridecyl)pyrrolidine: A Defense Alkaloid of the Mexican Bean Beetle

Abstract

The synthesis of (2S,12′R)-2-(12′-aminotridecyl)pyrrolidine [(S,R)-8], a defense alkaloid of the Mexican bean beetle Epilachna varivestis starting from (R)-proline is described. The second stereogenic center is generated by nucleophilic 1,2-addition of methyllithium to an aldehyde-SAMP-hydrazone, followed by reductive N-N bond cleavage. The product is obtained in good yield and high enantiomeric and diastereomeric purity.