Asymmetric Lithiation-Substitution Sequences of Functionalized Allylic and Benzylic Amines Mediated by (-)-Sparteine

Abstract

Modification of the allyl amine with selected substituents at the beta and gamma-positions allowed for an examination of yields, product distributions, enantioenrichments, mechanistic understanding and synthetic applications. With an extended allyl amine, enantioenriched diene products were obtained which participated in highly selective Diels-Alder cyclizations. Methyl substitution at the beta-position gave a substrate suitable for mechanistic studies. The addition of a heteroaromatic ring on the allyl backbone provided a substrate that behaved very similarly to the cinnamyl analogue. The robust nature of the furan ring was observed as a variety of conditions needed for enecarbamate transformations did not affect the ring stability.