Synthesis of palladium(II) 3d-metal(II) paddlewheel acetate-bridged heterodimetallic complexes: Unexpected catalysis by water molecules

The reaction of Pd 3 (μ-OOCMe) 6 ( 1 ) with 3d-metal acetates (Ni II , Co II , Cu II ) in acetic acid is triggered by the primary hydrolytic cleavage of an acetate bridge in molecule 1 , affording 1D polymeric complexes {Pd(μ-OOCMe) 4 M(OH 2 )(HOOCMe) 2 } n built of the paddlewheel units [Pd(μ-OOCMe) 4 M] linked trough the H-bonded H 2 O and MeCOOH molecules. A study of the reaction kinetics between the trinuclear palladium(II) acetate Pd 3 (μ-OOCMe) 6 ( 1 ) and the mononuclear 3d-metal (Ni II , Co II , Cu II ) acetates in acetic acid under water-specified conditions revealed a fairly complicated reaction mechanism triggered by the primary hydrolytic cleavage of an acetate bridge in molecule 1 . The isolated reaction products, as established by X-ray diffraction study, are 1D polymeric complexes {Pd(μ-OOCMe) 4 M(OH 2 )(HOOCMe) 2 } n (M = Ni II , Co II , Cu II , Mn II , Zn II ) built of the Pd II -based paddlewheel units [Pd(μ-OOCMe) 4 M] and linked trough the H-bonded H 2 O and MeCOOH molecules.