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چکیده
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Two mononuclear coordination complexes of fullerene[60] with Pd(dba)2 (dba= dibenzylideneacetone), [(η2-C60)Pd(Ph2P(CH2)2PPh2=C(H)C(O)R)2] (R= C10H7 (1), C6H4Cl(2)), have been prepared through a simple procedure to explore new directions in palladium catalysis and nanocarbon chemistry. The palladium(0)-[60]fullerene complexes incorporating unsymmetrical phosphorus ylides have been characterized by 1H, 13C and 31P NMR spectroscopic methods and other conventional techniques such as IR, TGA, SEM, ICP-OES, EDX and TEM analysis. Attributed to the enhanced dispersity and uniform size of Pd nanoparticles with phosphine-functionalized fullerenes, the prepared catalysts exhibited comparable catalytic activity to those reported for Mizoroki-Heck coupling reaction of aryl chlorides. Because of their abundance and low cost, aryl chlorides are the most desirable substrates from an industrial point of view in Csp2-Csp2 coupling reactions. Furthermore, overall bonding modes in the palladafullerenes of bifunctional diphosphine-based ligands were investigated by spectroscopic analysis and theoretical calculations. DFT studies of geometryoptimized monodentate and bidentate structures for 1 were calculated at the B3LYP/LANL2MB level of theory to understand the origin of the observed coordination modes.
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