Transition metals, binding

The fact that imidazole (Him) residues are particularly popular transition metal binding sites within metalloproteins is a major driving force for investigations of this heterocycle. The divalent... 

The orientation of molecules at the interface depends on an interaction with both the surface and the molecules in the liquid phase, and also on the interaction within the adsorbed layer. The interaction of molecules with the electrode is stronger the weaker their interaction with other molecules in the bulk. The correlation between and 0 is linear but different for the transition metals and the sp metals. Owing to the tendency to form chemisorption bonds, transition metals bind water molecules more strongly than the sp metals. 

What is the effect of d orbitals on the binding energy It is known that transition metals bind hydrogen in two different ways (1) as an intact molecule (39) or (2) as the insertion product (40). The common explanation is that the type of binding depends upon the nature of M, i.e., its ability to back-donate electrons from filled... 

In addition to structure stabilization and catalytic applications, transition metal-binding sites may be designed and exploited for regulatory purposes. For example, a regulatory metal-binding site has been engineered into the active site of trypsin, where metal binding inhibits proteo-... 

Fujita s group has produced a number of molecular capsules through careful consideration of transition metal binding requirements [17]. Threefold coordination around a metal can lead to ligands diverging at 90° or 109.5° to generate tetrahedral or cubic capsules, respectively. 

Transition metals bind to the face of an alkene. Therefore the orbitals of interest are the filled l7t (bonding) orbital and the empty 271 (antibonding) orbital of the C=C double bond (Figure 1.18). The actual energies of these orbitals will depend on the nature of the alkene substituents,... 

Another example described in Section 9.5.3 reports the synthesis and screening of a synthetic receptor library aimed at transition metal binding. Other similar examples have been reported recently. Burger and Clark Still (211) prepared ionophoric, cyclen-based libraries decorated by amino acid units and screened them for their ability to complex copper and cobalt ions Malin et al. (212) identified novel hexapeptidic technetium-binding sequences from the screening of cellulose-bound libraries and... 

Chart J, Kan CT, Jeffery Leigh G, Pickett CJ, Stanley DR (1980b) Transition-metal binding sites and ligand parameters. J Chem Soc Dalton Trans 1980 2032-2038 Chen QW, Chen CL (2005) The role of inorganic compounds in the prebiotic synthesis of organic molecules. Curr Org Chem 9 989-998... 

Ian Atkinson is based at lames Cook University in Queensland where his research interests lie in the application of high performance computing tochemkal problems. He has undertaken computational studies across a number of areas that include thermodynamic and chemical aspects of transition metal binding to substrates, self-assembly in supramoiecular chemistry and crystal engineenng... 

Molecular magnetism constitutes another promising facet of modem coordination chemistry and the field has produced in recent years both magnificent solid-state structures and properties. The use of transition metal binding sites associated with various luminophores, for instance has also led to the development of promising molecular switches. 

Conjugated enynes possess several of the same transition metal binding modes exhibited by their diyne counterparts, including Jt-coordination, a-carbenoid formation, and a/jt metal complexation (Scheme 35). In some cases, these constructs are very stable and can be isolated, but they are frequently transient structures in which the metal ion acts as a catalyst for enyne cycloisomerisation and ligand transformation reactions. 

Barsdate, R.J., 1970. Transition metal binding by large molecules in high latitude waters. In D.W. Hood (Editor), Symposium on Organic Matter in Natural Waters. Inst. Mar. Sci., Univ. Alaska, Occ. Publ., 1 485—491. 

A comparison of hammerhead ribozyme structures solved in the presence of 0.1 M Zn, Co, or Cd shows that in addition to other sites also occupied by Mg, the transition metals bind at an additional site within 2.5 A of the N7 of position G5, a position relatively exposed to solvent.A Cd site including guanine N7 and a rare sugar 2 -OH as ligands has been modeled in a 2.6 A structure of a 23S rRNA subdomain bound to ribosomal protein Lll a different structure of this same RNA was also found to contain a site (see Section 8.29.4.2). 

The transition metal binds a chiral ligand to give a chiral catalyst... 

Sason My intentions are very focused. I will teach the Law of Nirvana for transition metals, and I will then show how many other atoms/groups must a transition metal bind to achieve electronic Nirvana. 

The geometrical isomers of the thiosemicarbazones of 2-formylpyridine (4) and 1-foimylisoquinoline (1) have been synthesized and their structures studied by spectroscopic methods [69]. X-Ray diffraction studies of bis(isoquinoline-l-carboxaldehyde thiosemicarbazanato)nickel(ll) monohydrate by Mathew and Palenik [49] have demonstrated that the transition metal binds with the thiol form (118) of the a-(AO-heterocyclic carboxaldehyde thiosemicarbazones. The... 

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