Bis[(2-methylacetatobenzyl)tri(p-tolyl)phosphonium]hexabromodipalladate(II); synthesis, characterization, structural study and application as a retrievable heterogeneous catalyst for the amination of aryl halides and Stille cross-coupling reaction

• Published in: Inorganica Chimica Acta 2016-05, Vol.446, p.97-102
• Main Authors: Ghorbani-Choghamarani, Arash, Naghipour, Ali, Heidarizadi, Fateme, Shirkhani, Roghayeh, Notash, Behrouz
• Format: Article
• Language: English
• Subjects: Amination reaction; Palladium(II) acetate; Phosphonium salt; Stille cross-coupling reaction
• ISSN: 0020-1693; 1873-3255
• DOI: 10.1016/j.ica.2016.02.045

In this research article bis[(2-methylacetatobenzyl)tri(p-tolyl)phosphonium]hexabromodipalladate(II) has been prepared and characterized by X-ray crystallography. This compound has been applied as catalyst for the amination and Stille cross-coupling reactions. [Display omitted] •(CH3C6H4)3PCH2C6H4CH2OC(O)CH32[Pd2Br6] was prepared.•This compound characterized by CHN, IR, 1H, 31P, 13C NMR and X-ray crystallography.•It showed good catalytic reactivity in amination and C–C coupling reactions. The treatment of tri(p-tolyl)phosphine with 1,2-bis(bromomethyl)benzene results in (2-bromomethylbenzyl)tri(p-tolyl)phosphonium bromide. The resulted phosphonium salt reacts with palladium acetate(II) in a molar ratio of 1.5:1, respectively, to give [(CH3C6H4)3PCH2C6H4CH2OC(O)CH3]2[Pd2Br6], bis[(2-methylacetatobenzyl)tri(p-tolyl)phosphonium]hexabromodipalladate(II), as a dark brown powder. Characterization of the obtained compound was performed by elemental analysis (CHN), IR, 1H, 31P, 13C NMR and X-ray crystallography techniques. This compound was found to be an efficient catalyst for the amination of aryl halides using aqueous ammonia to produce primary amines and for Stille cross-coupling reaction to produce biphenyl and its derivatives as well. Describe catalyst showed satisfactory results and could be recovered and reused without significant loss of its catalytic activity in both reactions.