Catalytic comparison of Pd-C60 complex and its non-fullerene form bearing phosphorus ylide in C[sbnd]C coupling reactions

Abstract

The new fullerene-based Pd complex [(η2‐C60) Pd(Y)2] (1) and its non-fullerene form [(Y)PdCl2] (2) bearing unsymmetrical phosphorus ylide [Ph2P(CH2)2PPh2 = C(H)C(O)C6H4-p-CH3] (Y) were prepared through dissolving Y in related solvent in the presence of [C60Pd]n polymer or PdCl2(cod) (cod = 1,5-cyclooctadiene), respectively. The synthesized compounds were characterized using NMR (1H, 13C, and 31P), IR, UV–Visible, XRD, EDX, TGA/DTG/DTA, and SEM/TEM techniques. The crystal structure of compound Y was also obtained by X-ray analysis. The data proved that fullerene (C60) and two ylides were coordinated to Pd(0) center in complex 1 through [6,6] bond and two free phosphorus atoms, respectively. Also, the reaction of the unsymmetric phosphorus ylide Y with PdCl2(cod) led to the PC chelated complex 2. Finally, the catalytic properties of synthesized complexes were studied on Suzuki-Miyaura and Mizoroki-Heck CC coupling reactions. By comparing catalytic properties of complexes, it was found that complex 1 including fullerene nanoparticle has more promising activity in CC coupling reactions.