An Improved Stereocontrolled Route to cis-Erythrinanes by Combined Intramolecular Strecker and Bruylants Reaction

Abstract

Condensation of (2-iodophenyl)ethylamines with cyclohexanoylacetaldehyde provided the corresponding aldimines which were reduced yielding secondary phenethylcyclohexanoylethylamines. These in turn were appropriate intermediates to prepare several erythrinanes by a sequential intramolecular Strecker and intramolecular Bruylants reaction. In contrast, the C-ring homologue schelhammeranes were not available on this route.