Total Synthesis of DL-Isoretronecanol and DL-Trachelanthamidine using Anodic Methoxylation in a Key Functionalizing Step.

Abstract
The title substances were synthesized in 6 steps from simple starting materials. The key step involved anodic functionalization of the tertiary amide 9 followed by an intramolecular amidoalkylation, thus creating the pyrrolizidine ring system in 11. The 2 diastereomeric pairs of compounds 4a and 4b were then separated by column chromatography. These lactams were reduced cleanly with retained stereochemistry to the title subtances 1a and 1b, respectively. An attempt at an intramolecular amidoalkylation of the monoester 3 resulted in the formation of an 0-alkylated product, the ketene acetal 6.