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Heck reaction of chloroarenes (I) with vinyl compounds (II) is accomplished using title nanoparticles as catalyst.

9]. Since the discovery of the BHAR (1995) [10,11], a range of modifications for this reaction has been developed to increase the reaction efficacy [12,13]. A survey in this field demonstrated that major advances have been obtained on developing new and more effective phosphorus ligands. The chemical structures of some of the used phosphorus ligands in BHAR are shown in Fig. 1 [14 -19]. It should be mentioned that some of these ligands have been showed high activity in BHAR.Despite the high activity of phosphorus ligands in metalcatalyzed organic reactions, they often suffer from some disadvantages, such as intrinsic toxicity, foul-smell, easy oxidization during reaction process, difficulty of extraction, tedious purification process, and lack of recoverability [20,21]. Stabilization of these ligands on a recyclable support is one of the most important approaches to improve their applicability in organic reactions [22][23][24]. However, separation and recovery of these ligands on solid supports usually required filtration or centrifugation; therefore, the efficiency of the recovered ligands can be somewhat reduced. In the recent years, magnetic nanoparticles (MNPs) have attracted much attention because of their easy preparation, large surface area ratio, facile separation by use of magnetic force, and low toxicity and price [25].Recently, in our research group, MNPs were functionalized using chlorodiphenylphosphine (ClPPh 2 ) and phosphine-functionalized magnetic nanoparticles (PFMN) as a recyclable phosphorus ligand were obtained [22]. Also, palladium (II) complex of PFMN ligand (Pd-PFMN) was prepared and its catalytic activity evaluated in the Heck reaction of chloroarenes. The results revealed that, this new catalyst showed high catalytic activity in the Heck reaction of chloroarenes [22]. This activity is attributed to the high reactivity of Pd complex involving phosphorus ligands and dispersible ability of MNPs in solution as a high surface Abstract The supported palladium on phosphine-functionalized magnetic nanoparticles (Pd-PFMN) was found to be an efficient magnetically separable catalyst for the Buchwald-Hartwig amination reaction (BHAR) under solvent-free conditions. All of the reactions in the presence of Pd-PFMN catalyst afforded the corresponding products in good to excellent yields. The catalyst can be easily separated from the reaction mixture using an external magnetic field, and it can be reused at least five cycles without significant loss in its initial catalytic activity.

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