2,2 -Bipyrimidine metal complexes

Shavaleev, N.M., Accorsi, G, Virgili, D., etal. (2005) Syntheses and crystal structures of dinuclear complexes containing d-block and f-block luminophores. Sensitization of NIR luminescence from Yb(III), Nd(III), and Er(III) centers by energy transfer from Re(I)- and Pt(II)-bipyrimidine metal centers. Inorganic Chemistry, 44, 61. 

The study of exchange interactions between transition-metal ions and copper(II) in particular has been an active field of research (Section 6.6.3.6).254-256 In this context, Verdaguer and co-workers investigated complexes (292) and (293), supported by flexible 2,2 -bipyrimidine.257... 

As observed in other oxo-centered triruthenium-acetate complexes, the electronic absorption spectra of 36 and dimer 37 with rt/zr -metal latcd 2,2 -bipyrimidine are... 

Oxidation of Methane. A variety of new catalyst systems have been disclosed, and new reagents were developed with the aim to perform selective transformation of methane to methanol, methyl esters, and formaldehyde. Much work was carried out in strongly acidic solutions, which enhances the electrofilicity of the metal ion catalyst, and the ester formed is prevented from further oxidation. An important advance in the selective oxidation of methane to methanol is Periana s 70% one-pass yield with high selectivity in sulfuric acid solution under moderate conditions.1073 The most effective catalyst is a Pt-bipyrimidine complex. Pt(II) was shown to be the most active oxidation state generating a Pt-methyl intermediate that is oxidized to yield the product methyl ester. A density functional study... 

Figure 2.47 Molecular structure of [ Nd(L )3(MeOH) 2(fi-bpm)]. Fluorine atoms and carbon-bound hydrogen atoms are omitted. Hydrogen bonds are shown as dashed lines [26a]. (Reprinted with permission from G. Zucchi, O. Maury, P. Thuery and M. Ephritikhine, Structural diversity in neodymium bipyrimidine compounds with near infrared luminescence from mono- and binuclear complexes to metal-organic frameworks, Inorganic Chemistry, 47, 10398-10406, 2008. 2008 American Chemical Society.)...

The crystal structures of three metal rhodizonato complexes were determined Rb2Cg Oe , prepared by reacting anhydrous rhodizonic acid with RbOH, and the other two , 108, prepared by reacting aqueous Na2C60e, with 2,2 -bipyrimidine and either Cd(N03)2 4H2O or MnCl2. 

The proposed mechanism for this methane oxidation is shown in Scheme 18.2 and follows steps discussed in more detail in the next section. One remarkable feature of this platinum system in this highly acidic medium at high temperatures is the thermodynamic stability of platinum(II) boimd by the bipyrimidine ligand. Addition of platinum metal to bipyrimidine in sulfuric acid leads to generation of the platinum(II) bipyrimidine complex (Equation 18.8). 

The failure of the mononuclear [Ru(bpy)2(py)OH2] to promote oxygen evolution followed by success of the blue dimer and the fact that the OEC itself contains a multi-metal centre, lead researchers to believe that multiple sites were required for catalytic water oxidation. However, the mechanism proposed for the activation of the blue dimer showed that in reality, only one of the metal centres is involved in the oxygen-oxygen bond formation step. This suggestion was later confirmed when Meyer and co-workers showed that single site ruthenium-aqua complexes were capable of oxidizing water in the presence of Ce(iv). One of these catalysts, [Ru(tpy)(bpm)OH2] " (tpy = terpyridine, bpm = 2,2 -bipyrimidine), is shown in Scheme 5.2. 

G1 Z, Maury O, Thuery P et al (2008) Structural diversity in neodymium bipyrimidine crunpounds with near inhared luminescence horn mono- and binuclear complexes to metal-OTganic liameworks. Inorg Chem 47 10398-10406... 

The synthesis of several Re(I)-nitrogen donor ligand complexes have been reported and the emissive nature of their metal-ligand charge transfer excited states discussed. Examples include [Re(CO)3CIL2] (L2 = bipy, phen and their derivatives, 2,2 -bipyrazine, or 2,2 -bipyrimidine), [ Re(CO)301)2(y-2,2 -... 

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