Polydopamine supported palladium nanoparticles: Highly efficient catalysts in Suzuki cross-coupling and tandem Suzuki cross-coupling/nitroarene reductions under green reaction conditions

•Pd nanoparticles as small as 1–3 nm supported on mussel-inspired polydopamine are used as catalyst.•Highly efficient Suzuki cross-coupling and one-pot tandem Suzuki cross-coupling/nitroarene reduction under green reaction conditions.•Pd-concentrations down to ppm level could be used.•Wide substrate scope and gram-scale synthesis of valuable substituted biphenyls and biphenyl anilines are described.