Catalytic [3+2] Annulation of Aminocyclopropanes for the Enantiospecific Synthesis of Cyclopentylamines

With nitrogen too: The first catalytic [3+2] annulation of aminocyclopropanes with enol ethers is reported (see scheme; Phth=phthaloyl). The reaction worked with easily accessible phthalimidocyclopropanes using 5 mol % of SnCl4 in nearly quantitative yields. Polysubstituted cyclopentylamines, which are often present in bioactive compounds, were obtained with high diastereoselectivity and enantiospecificity.