Multicomponent reactions are arguably one of the most powerful methods for diversity-oriented synthesis. These step-economical strategies have been embraced by medicinal chemists to expand the chemical space evaluated in biological screening and drug discovery, and are predicated on constructing a common structural core from easily diversified building blocks. These reactions commonly proceed via a cascade of elementary chemical steps. Nevertheless, orthogonal functionality and undesirable cross-reactivity between reaction components are key limiting factors when designing appropriate synthons and conditions. Amidines are a prominent class of bioactive compounds found in a wide variety of natural products (scheme 1.a). Due to their common structural core decorated with three substituents, amidines are perfect candidates for multicomponent synthesis. Their unique structural features, stemming from a conjugated amine core, are at the root of numerous applications. In addition to their broad use as bioactive pharmacophores, amidines are synthetic intermediates for heterocyclic compounds and useful ligands for metal complexes. Nevertheless, none of the existing synthetic methodologies afford amidines with three aromatic substituents. Thus, the design of a multicomponent , single-step reaction to afford a diverse array of amidines, especially those with three aromatic substituents decorating the conjugated amine core, is both synthetically challenging and appealing as a gateway to numerous untapped applications. In light of the above-mentioned considerations, it is not surprising that amidine synthesis has received attention in recent years. Initial studies were based on the reactivity between enamines and sulfonyl azides; however, this methodology depended on the isolation of stable enamine substrates (Scheme 1.b. top left). In the following years, focus shifted to organometallic catalysis. Furber and coworkers developed a palladium-catalyzed multicomponent amidine synthesis from secondary amines, tert-butyl isonitrile, and substituted bromobenzene (Scheme 1.b. top right). However, this transformation required the addition of stoichiometric amounts of base (Cs2CO3), and the substrate scope was limited mostly to aliphatic secondary amines and only one example of isonitrile precursor was presented. Chang and coworkers reported a copper-catalyzed multicomponent oxidative amination, which offers practical access to sulfonyl amidines from alkyl amine, azide and alkyne building blocks (Scheme 1.b. bottom right). Zhang and coworkers reported a one-pot two-step rhodium-catalyzed amidine synthesis, wherein isonitriles were reacted with azides forming carbodiimides, to which boronic acids were added to afford amidine products (Scheme 1.b. bottom left). The scope of this reaction was limited to tert-butyl, cyclohexyl and 2,6-dimethylphenyl isonitrile, and only allylic and aromatic boronic acids were used. Overall, despite the great progress these and other metal-catalyzed methodologies represent in the multicomponent synthesis of amidines, they still rely on the preparation of building blocks that are often not readily accessible such as isonitriles, aldoximes, and terminal alkynes. Table . Perturbations to optimal reaction conditions Inspired by the metal-free approach for the formation of sulfonyl amidines through a reaction between enamines and azides (Scheme 1.b.), we envisioned a new strategy for amidine synthesis. Herein, based on the in situ formation of enamines by the addition of amines to ketones, we disclose a three-component, one-step, metal-free strategy to afford sulfonyl amidines from readily accessible reagents. To the best of our knowledge, this is the first transformation in which three aromatic substituents could be connected to the amidine core in a single step.