Isolable C@Fe3O4 nanospheres supported cubical Pd nanoparticles as reusable catalysts for Stille and Mizoroki-Heck coupling reactions

•An efficient heterogeneous catalyst Pd cNPs/C@Fe3O4 was developed.•Stille and Mizoroki-Heck coupling reactions were performed with good yield.•Facet dependent catalytic activity of Pd cNPs and Pd sNPs were studied.•Wide substrate scope, magnetically recyclable and gram scale operation.•Alternative synthetic strategies for construction of biaryl and diphenylethene.