REACTIVITY OF THE CYCLIC TETRANUCLEAR COMPLEX [PD4(MU-O-C6H4)2(MU-O2CME)4(MU-SPR(I)2)2]

Bridge splitting reactions of the cyclic tetranuclear complex, [Pd4(mu-o-C6H4)2(mu-O2CMe)4(mu-SPri2)2], with neutral and anionic ligands afforded a variety of dinuclear palladium(II) complexes. In addition to the common one bridging o-phenylene ligand, the products contained different bridging ligands depending upon the ligand used. Dpm (Ph2PCH2PPh2) or btmp (PhCH2SCH2PPh2) acted as bidentate bridging ligands to give [Pd2(mu-o-C6H4)(O2CMe)2(mu-L2)2] (L2=dpm, btmp). In contrast, Me2bpy (4,4'-dimethyl-2,2'-bipyridyl) behaved as a bidentate chelating ligand to afford a cationic complex bearing the mu-acetato ligand, [Pd2(mu-o-C6H4)(mu-O2CMe)(Me2bpy)2](MeCO2). In the case of Tl(acac), the acac ligand coordinated in a bidentate chelating fashion to yield a mu-sulfide complex, [Pd2(mu-o-C6H4))(acac-O, O')2(mu-SPri2)]. This complex further reacted with 3,5-lutidine to give [Pd2(mu-o-C6H4))(acac-O, O')2(3,5-lut)2]. Complexes obtained here were characterized by means of elemental analyses, NMR and IR spectroscopies.