A novel and task-specific nano-magnetic Schiff base ligand with phosphate spacer using 2-aminoethyl dihydrogen phosphate instead of usual coating agents, i.e. tetraethoxysilane and 3-aminopropyltriethoxysilane, for coating of nano-magnetic Fe3O4 is introduced. The nano-magnetic Schiff base ligand with phosphate spacer as a novel catalyst was synthesized and fully characterized using infrared spectroscopy, X-ray diffraction, scanning and transmission electron microscopies, thermogravimetry, derivative thermogravimetry, vibrating sample magnetometry, atomic force microscopy, X-ray photoelectron spectroscopy and energydispersive X-ray spectroscopy. The resulting task-specific nano-magnetic Schiff base ligand with phosphate spacer was successfully employed as a magnetite Pd nanoparticle-supported catalyst for Sonogashira and Mizoroki–Heck C–C coupling reactions. To the best of our knowledge, this is the first report of the synthesis and applications of magnetic nanoparticles of Fe3O4@O2PO2(CH2)2NH2 as a suitable spacer for the preparation of a designable Schiff base ligand and its corresponding Pd complex. So the present work can open up a new and promising insight in the course of rational design, synthesis and applications of various task-specific magnetic nanoparticle complexes.