Progress toward the synthesis of apomorphine: Chiral auxiliary mediated interception of an intramoleculary formed N-acyl iminium ion.

摘要

Glaucine, which contains an aporphine skeleton, has been previously synthesized utilizing an intermolecular approach to form an iminium ion for the Pictet-Spengler reaction. A diastereomeric excess of 79% resulted as mediated by a chiral auxiliary. Progress was made in attempting to increase the diastereomeric excess by using an intramolecular approach to iminium ion formation. Apomorphine is a suitable platform on which to demonstrate the asymmetric interception of a chiral N-acyl iminium ion generated by intramolecular means.; Several routes to this end were explored. These routes included the use of an intramolecular variant on the previously published work, Grubbs' metathesis and Horner-Wadsworth-Emmons among others. While no route proved successful in the end, understanding of the formation of aporphine skeletons was expanded upon.