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 [Fe-3(CO)(12)], [Rh(CO)(2)Cl](2) and PdCl2 resulted in three new mononuclear complexes, {Fe(CO)(4)(n(1)-(P)-PPh2(p-C6H4NMe2)]} (1a), trans-{Rh(CO)Cl[n(1)-(P)-PPh2(p-C6H4NMe2)](2)} (2) and trans-{PdCl2[n(1)-(P)-PPh2(p-C6H4NMe2)](2)} (3), respectively. A small amount of dinuclear nonmetal-metal bonded complex, {Fe-2(CO)8[mu,-(P,N)-PPh2(p-C6H4NMe2)]} (1b), was also isolated as a side product in the reaction of (Fe-3(CO)(12)]. The complexes were characterized by elemental analyses, mass, IR, UV-vis, H-1, C-13 (except 1b) and P-31{H-1} 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 (C) 2011 John Wiley & Sons, Ltd.