Support-Free Palladium–NHC Catalyst for Highly Recyclable Heterogeneous Suzuki–Miyaura Coupling in Neat Water

Among the various new challenges of chemical processes in water, research on stable, highly active, and recyclable catalysts is a prosperous field. We present here a palladium–NHC catalyst that was synthesized with good yields through a series of simple synthetic steps. This organometallic species was used as a heterogeneous catalyst in low loadings for Suzuki–Miyaura coupling in neat water, under mild conditions. Reaction conditions were optimized for a simple, green, and support-free procedure, without using any phase transfer agent. The catalyst shows excellent reactivity in short times toward different substrates and a very good recyclability.