A One Pot Photochemical Method for the Generation of Functionalized Aminocyclopentanes

Detailed herein is the development of a photochemical intermolecular formal [3+2] cycloaddition between cyclopropylimines and substituted alkenes to generate cyclopentylimines. The Schiff base auxiliary of the cyclopropylimine was designed to enable a masked N-centered radical approach in which the requisite open-shell character was achieved upon excitation with violet light. The cycloaddition products were directly converted to N-functionalized aminocyclopentanes via N-acylation and solvolysis, thus offering a three-step, one-pot procedure for the production of diversely-substituted aminocyclopentanes. The photochemical component of this reaction sequence was demonstrated to operate in continuous flow and was amenable to gram-scale production.