Iron(0), rhodium(I) and palladium(II) complexes with p-(N,N-dimethylaminophenyl) diphenylphosphine and the application of the palladium complex as a catalyst for the Suzuki–Miyaura cross-coupling reaction



The reaction of p-(N,N-dimethylaminophenyl)diphenylphosphine [PPh2(p-C6H4NMe2)] with [Fe3(CO)12], [Rh(CO)2Cl]2 and PdCl2 resulted in three new mononuclear complexes, {Fe(CO)41-(P)-PPh2(p-C6H4NMe2)]} (1a), trans-{Rh(CO)Cl[η1-(P)-PPh2(p-C6H4NMe2)]2} (2) and trans-{PdCl21-(P)-PPh2(p-C6H4NMe2)]2} (3), respectively. A small amount of dinuclear nonmetal-metal bonded complex, {Fe2(CO)8[µ-(P,N)-PPh2(p-C6H4NMe2)]} (1b), was also isolated as a side product in the reaction of [Fe3(CO)12]. The complexes were characterized by elemental analyses, mass, IR, UV–vis, 1H, 13C (except 1b) and 31P{1H} NMR spectroscopy. The Pd complex 3 effectively catalyzes the Suzuki–Miyaura cross-coupling reactions of aryl halides with arylboronic acids in water–isopropanol (1:1) at room temperature. Excellent yields (up to 99% isolated yield) were achieved. The effects of different solvents, bases, catalyst quantities were also evaluated. Copyright © 2011 John Wiley & Sons, Ltd.