Visible-light-activated photocatalyst- and additive-free multi-component reaction driven by the cyclopropylamine-based EDA complex in water†

Abstract

Green synthesis involving visible-light EDA chemistry, multi-component systems and water as a medium is highly attractive and desirable in academia and industry. Herein, we offer a protocol to achieve a photocatalyst- and additive-free multi-component reaction driven by a cyclopropylamine-based EDA complex in water. A mechanistic study revealed that electron-deficient alkenes served as electron acceptors, enabling the formation of an EDA complex with cyclopropylamine. A series of cyclopentylamines derived from readily available cyclopropylamine, aldehyde and activated methylene species can be provided in moderate to excellent yields (up to 93%). The applicability of this method has been further demonstrated in the late-stage functionalization of a number of commercially available pharmaceutical compounds and exploration of their derivatization.