Visible-light photocatalytic metal-free multicomponent Ugi-like chemistry

The possibility of harnessing the photoactivity of isocyanides in the development of metal-free Ugi-like visible light photo-triggered multicomponent transformations has been reported herein. More in detail, Ugi-3CR, Ugi-Tetrazole-3CR, and UgiJoulli-3CR afforded imide peptidomimetic derivatives in good yields and with a wide substrate scope, involving the late-stage editing of complex bioactive scaffolds. Furthermore, a 2-step-one-pot sequence affording linear secondary imides, and a 3-step-one-pot protocol leading to densely functionalized bis-amide derivatives have also been developed to highlight the huge potential of these mild metal-free reaction conditions to afford complex and diverse compounds while being in accordance with the green chemistry principles . The direct photoexcitation of isocyanides is able to trigger a collection of Ugi-like multicomponent reactions under metal-free conditions and in the absence of any additives starting from both linear and cyclic tertiary aromatic amines.