Asymmetric synthesis of 3,5-disubstituted indolizidines by intermolecular addition of an allylsilane on an N-acyliminium ion

Abstract A diastereoselective synthesis of 3,5-disubstituted indolizidines based on an intermolecular addition of an allylsilane on an acyliminium ion derived from ( S )-pyroglutamic acid is described. The synthetic potential of this methodology is demonstrated by the enantioselective synthesis of (−)-indolizidine 195B, (−)-indolizidine 223AB, (+)-monomorine and (−)-3-butyl-5-propyl indolizidine.