Modular Synthesis of Heterobenzylic Amines via Carbonyl Azinylative Amination

Abstract

AbstractTransformations enabling the synthesis of α‐alkyl, α′‐2‐azinyl amines by addition of 2‐heteroaryl‐based nucleophiles to in situ‐generated and non‐activated alkyl‐substituted iminium ions are extremely rare. Approaches involving classical 2‐azinyl organometallics, such as the corresponding Grignard reagents, often fail to produce the desired products. Here, we report an operationally straightforward solution to this problem through the development of a multicomponent coupling process wherein a soft 2‐azinyl indium nucleophile, generated in situ from the corresponding 2‐iodo heteroarene and indium powder, adds to an iminium ion that is also formed directly in the reaction. This modular carbonyl azinylative amination (CAzA) displays a broad scope and only a metal reductant is needed to generate a reactive 2‐azinyl nucleophile. Beyond the addition to iminium ions, the 2‐azinyl addition to polyfluoromethyl ketones forms the corresponding tertiary alcohols. Together, the products of these reactions possess a high degree of functionality, are typically challenging to synthesize by other methods, and contain motifs recognized as privileged in the context of pharmaceuticals and agrochemicals.