Polynuclear transition metal complexes, which are embedded in the active sites of many metalloenzymes, are responsible for effecting a diverse array of oxidation reactions in nature. The range of chemical transformations remains unparalleled in the laboratory. With few noteworthy exceptions, chemists have primarily focused on mononuclear transition metal complexes in developing homogeneous cata...

The asymmetric unit of the title complex, [Cu(2)(C(8)H(4)NO(6))(2)Cl(2)(C(10)H(8)N(2))(2)]·2H(2)O, contains two half binuclear complex molecules and two solvent water molecules; the complete complex molecule is generated by the application of a centre of inversion in each case. Each independent Cu(II) cation is penta-coordinated within a distorted square-pyramidal environment defined by a two μ...

Delivery agents which can carry the {Ru(NO)}(6) chromophore ("caged NO") are desired for vasodilation and for photodynamic therapy of tumors. Toward these goals, complexes derived from [RuCl(3)(NO)(H(2)O)(2)]= (1) have been prepared using dipyridylamine (dpaH) as mono and bis adducts, [Ru(NO)Cl(3)(dpaH)] = (2) and [Ru(NO)Cl(dpaH)(2)]Cl(2) = (3). The dpaH ligands coordinate cis to the Ru(NO) axi...

The synthesis and structures of two new octadentate, Schiff-base calixpyrrole macrocycles are presented in which modifications at the meso-substituents (L(1)) or the aryl spacer between the two pyrrole-imine donor compartments (L(2)) are introduced. The outcomes of these changes are highlighted in the structures of binuclear Pacman complexes of these macrocycles, [M(2)(L(1))] and [M(2)(L(2))]. ...

Multinuclear manganese sites that are involved in the catalysis of reactions vital to biological systems are being steadily recognized and studied. Besides the photosynthetic water-oxidizing complex, which is known to utilize 4 Mn ions for the oxidation of water to molecular oxygen [1], evidence has accumulated that the Mn site of the pseudo-catalase from Lactobacillus planatrum is comprised of...

The isospecific 3,4-polymerization of isoprene has been achieved for the first time by use of a combination of a binuclear rare earth metal dialkyl complex, such as [Me2Si(C5Me4)(mu-PCy)YCH2SiMe3]2 (Cy = cyclohexyl), and an equimolar amount of [Ph3C][B(C6F5)4] as a catalyst system. A DFT calculation suggested that a binuclear monocationic monoalkyl species, such as [Me2Si(C5Me4)(mu-PCy)Y(mu-CH2...

ABSTRACT A series of dioxygen complexes of copper, iron, and manganese have been synthesized using bulky tripodal nitrogen ligands, hydrotris(3,5-dialkyl1-pyrazolyl)borate, as models for the active sites in the metalloproteins. A binuclear copper peroxo complex having p-q2:$ coordination mode serves as an accurate model of the active site of oxy-hemocyanin. The reactivities of the complex and r...

The title compound, [Mn2(C6H5COC6H4COO)2(C10H8N2)4](ClO4)2, comprises a centrosymmetric binuclear cation and two perchlorate anions. In the complex cation, two Mn(II) atoms are bridged by two O atoms of two different 2-benzoyl-benzoate ligands, each Mn(II) atom being further coordinated by two 2,2'-bi-pyridine (bipy) ligands in a distorted octa-hedral environment. Within the binuclear mol-ecule...