Studies on Transition Metal Complexes

In this section, we present some applications of DFT-based methods to the characterization of the structural, electronic, and dynamic properties of metal complexes of pharmaceutical inter- 

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Chemical applications of magnetic anisotropy studies on transition metal complexes. S. Mitra, Prog. Inorg. Chem., 1977, 22, 310-408 (160). 

Structural studies on transition metal complexes containing a-bonded carbon atoms Conformations of medium rings... 

Mitra, S., Chemical Applications of Magnetic Anisotropy Studies on Transition Metal Complexes. 22 309... 

Continuing a long series of kinetic and mechanistic studies on transition metal complexes, rischer et al have published a detailed account of the reaction between... 

Other recent PRDDO studies on transition metal complexes include an examination of inversion barriers in metal-phosp-hido complexes. such a.s Cp2ClTiP4)2, and substituent effects in trifluoromethyl[tris(pyrazoly)J borate complexes. ... 

The ENDOR techniques, of course, are not confined to studies of transition metal complexes. A fast growing interest on electron nuclear double and multiple resonance experiments is also noticed in other fields of natural sciences, such as radical, radiation and polymer chemistry, solid state physics, biophysics and mineralogy. 

In contrast to the free-radical polymerizations, there have been relatively few studies on transition metal catalysed polymerization reactions in water. This is largely due to the fact that the early transition metal catalysts used commercially for the polymerization of olefins tend to be very water-sensitive. However, with the development of late transition metal catalysts for olefin polymerizations, water is beginning to be exploited as a medium for this type of polymerization reaction. For example, cationic Pd(II)-bisphosphine complexes have been found to be active catalysts for olefin-CO copolymerization [21]. Solubility of the catalyst in water is achieved by using a sulfonated phosphine ligand (Figure 10.5) as described in Chapter 5. 

A great deal of emphasis has been placed on the study of transition-metal complexes containing two or more metal centers. These complexes are useful as model systems for the study of intermolecular interactions between metal centers as well as the examination of electron-transfer reactions between donor and acceptor species. 

In addition, a few other publications also address this issue of ballistic modification of composite propellants. The cobalt, nickel and zinc hexammine perchlorates have been studied by Gurdip Singh and coworkers for this purpose. The generated data indicate that cobalt complex accelerates burn rate three-fold when used at 2% level in HTPB-AP-based composite propellant [277]. Another study on transition metals (copper, iron, cobalt and nickel) salts of NTO as BRMs for HTPB-AP-based... 

Numerous physical properties are studied with transition metal complexes as the subjects, and many of them involve the use of ligand field theory in their interpretation. They vary from those such as the spectra and magnetic properties, which are heavily dependent on ligand field theory, to others such as reaction kinetics where the application of the theory is rather peripheral. 

BINOL and its derivatives have been utilized as versatile chiral sources for asymmetric catalysis, and efficient catalysts for their syntheses are, ultimately, required in many chemical fields [39-42]. The oxidative coupling of 2-naphthols is a direct synthesis of BINOL derivatives [43, 44], and some transition metals such as copper [45, 46], iron [46, 47] and manganese [48] are known as active metals for the reaction. However, few studies on homogeneous metal complexes have been reported for the asymmetric coupling of 2-naphthols [49-56]. The chiral self-dimerized V dimers on Si02 is the first heterogeneous catalyst for the asymmetric oxidative coupling of 2-naphthol. 

An interesting study of the electron affinity of different ligands as well as comparisons between inner and outer ligands in iridium-complexes was reported by W. Nefedow, 45) demonstrating clearly that XPS can furnish a lot of valuable information on transition metal complexes and organometallic compounds in general. 

The most important component of any solar energy conversion device is, of course, the photosensitizer. In this paper we will try to illustrate briefly our current studies on the search for new photosensitizers based on transition metal complexes. 

Griffith (1962) — modem synthetic studies on transition metal cyanide complexes. 

Consequently, to narrow the definition a bit further, we will adhere to Negishi s suggestion and define cross-coupling reactions as those that follow some variation of the mechanism depicted in Scheme 1 (where Mt is a transition metal, L is an ancillary hgand see Ancillary Ligand), and n is the oxidation state of the reduced metal in the catalytic cycle). This mechanism is supported by stoichiometric studies on isolated metal complexes (mostly where Mt = Pd, n = 0, L = triphenylphosphine) thought to be the intermediates in this cycle. 

For the reader desiring more information on mono-olefin complexes of the transition metals, a number of excellent reviews are available. Early studies on olefin-metal complexes (primarily of Pt, Pd, Ag, and Hg) have been reviewed by Keller Chatt 27), and Douglas 70). Two more... 

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