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Thiolating review

A brief review has appeared covering the use of metal-free initiators in living anionic polymerizations of acrylates and a comparison with Du Font s group-transfer polymerization method (149). Tetrabutylammonium thiolates mn room temperature polymerizations to quantitative conversions yielding polymers of narrow molecular weight distributions in dipolar aprotic solvents. Block copolymers are accessible through sequential monomer additions (149—151) and interfacial polymerizations (152,153). [Pg.170]

Thiol—Disulfide Interchange Reactions. The interchange between thiols and disulfides has been reviewed (50). This reaction is base-catalyzed. It involves the nucleophihc attack of a thiolate ion on a disulfide. This is shown in equations 35, 36, and 37. [Pg.13]

The chemistry of tetrazolium thiolates and other mesoionic tetra-zoliums has been extensively reviewed.297,298 Tho ugh there are no reports of the chemical reduction of thiolates to formazan-like structures, the polarographic reduction of the complex betaines (146) to formazans has been reported.655... [Pg.256]

Thiolate-bridged dinickel complexes and, in particular, heterobimetallic Ni/Fe complexes have attracted much interest as model systems for the hydrogenase enzymes. A review covering this... [Pg.443]

Reviews on mercury—thiolate complexes and their bio-relevance333 and complexes with steric-ally hindered thiolate ligands have been published.334... [Pg.1283]

Technetium complexes with thioethers in the strict sense, i.e., those without other donor groups in the ligand molecule, comprise homoleptic thioether nitridotechnetium(V) complexes [111], cationic mixed thioether/thiolate complexes of Tc(III) [112], and a cationic Tc(I) complex [113]. However, these latter compounds do not properly fall within the scope of Tc(V) compounds and are excluded from review. [Pg.99]

Rhodium complexes with chiral dithiolato and dithiother ligands have been studied in rhodium-catalyzed asymmetric hydroformylation. In all instances, enantioselectivities were low.391-393 Catalysis with compounds containing thiolate ligands has been reviewed.394... [Pg.176]

During the cross-couplings to form C—N, C—O, C—S, and C—P bonds, the arylpalladium halide complexes are converted to arylpalladium amide, alkoxide, thiolate, and phosphide complexes. Examples of each type of complex have now been isolated, and the reductive elimination of the organic products has been studied. Although the reductive elimination to form carbon-hydrogen and carbon-carbon bonds is common, reductive elimination to form carbon-heteroatom bonds has been studied only recently. This reductive elimination chemistry has been reviewed.23... [Pg.391]

The aim of this chapter is to review the chemistry of chalcogenolates in the last 10 years. The more recent reviews in this field included chalcogenolates of the s-block elements,13,14 early transition metal thiolates,15 metal complexes with selenolate and tellurolate ligands,16 copper(I), lithium and magnesium thiolates,17 functionalized thiolate complexes,18 19 pentafluorobenzenethiolate platinum group compounds,20 tellurium derivatives,21 luminescent gold compounds,22 and complexes with lanthanide or actinide.23... [Pg.33]

In an article published independently at the same time, Stuehr and Ikeda-Saito89 used the purified bNOS and iNOS to reach the same conclusions. While the paper was under review, the authors mention that White and Marietta had reported earlier that the iron was a heme and was used as an oxidant. Using the same type of study, they found that the iron prophyrin and its CO derivative had the expected properties and proposed that the iron is penta-coordinated, with a cysteine thiolate as the fifth coordinate. A third publication confirmed the results when McMillan and coworkers90 used bNOS grown in human kidney cells. These workers obtained similar data for the light absorption of the enzyme and its CO spectrum. They also speculate on very similar sequences in the three types of purified enzyme that might be the porphyrin binding site. [Pg.984]

Transition metal complexes of sterically hindered thiolate ligands have been reviewed. " These ligands give rise to unusual geometries and oxidation states, and low coordination numbers in their complexes. [Pg.833]

Sharma and Reed, 1976)]. In proteins the coordination number 4 is most common, where the zinc ion is typically coordinated in tetrahedral or distorted tetrahedral fashion. The coordination polyhedron of structural zinc is dominated by cysteine thiolates, and the metal ion is typically sequestered from solvent by its molecular environment the coordination polyhedron of catalytic zinc is dominated by histidine ligands, and the metal ion is exposed to bulk solvent and typically binds a solvent molecule (Vallee and Auld, 1990). The inner-sphere coordination number of catalytic zinc may increase to 5 during the course of enzymatic turnover, and several five-coordinate zinc enzyme—substrate, enzyme product, and enzyme-inhibitor complexes have been studied by high-resolution X-ray crystallographic methods (reviewed by Matthews, 1988 Christianson and Lipscomb, 1989). The coordination polyhedron of zinc in five coordinate examples may tend toward either trigonal bipyramid or octahedral-minus-one geometry. [Pg.286]

The electrochemical synthesis of cadmium and zinc thiolate complexes and their properties were reviewed in addition to other metal ion complexes [152]. [Pg.779]

The electrophilic reactions of NP with SH- and several SR- have been studied and reviewed (28). The nature of the reversible addition reactions [Eq. (5)] are reasonably well understood for the thiolates. A kinetic study including some bioinorganically relevant nucleophiles (cysteine, glutathione) was performed by using stopped-flow and T-jump techniques (77). The rate constants for the forward and reverse processes in Eq. (5) were in the range 103-104 M-1 s-1 and 101 K)3 s-1 at 25 °C, respectively. [Pg.111]

The following nomenclature has been used in this review The ring system is named as the appropriate heterocation and the exocyclic group carrying the negative charge is named as the appropriate anion (i.e., olate, thiolate, aminide, or methylate). Thus, compounds of type 9 are named as... [Pg.10]

Sulfur, thiolates and sulfide ligands form very stable complexes with platinum. Many complexes have platinum in the divalent state, but complexes with a Pt—S bond are formed with platinum in the zerovalent or tetravalent state. Several recent reviews have been written on various aspects of the platinum coordination chemistry of sulfur heteroatom ligands, and these are listed in Table 9. [Pg.471]

Gold(I) thiolates have important applications in gold coating and in the treatment of rheumatoid arthritis. There has been intensive research on these complexes, and excellent reviews have been published.9-14 The reader is referred to Chapter 62.2 for a review of medicinal applications. [Pg.875]

The biochemistry and medicinal chemistry of the gold(I) thiolates used in chrysotherapy have been thoroughly reviewed elsewhere9"14,240 and this account will deal only with stability and ligand exchange reactions of the gold(I) thiolates of interest to coordination chemists. [Pg.876]

Several reviews on gold therapy have appeared recently, with an emphasis on metabolism by Shaw,19 on ligand exchange reactions by Sadler and coworkers,20 on EXAFS and XANES studies by Elder et al.,21 and on studies of gold thiolate complexes in vivo and in vitro by Brown and Smith.22... [Pg.759]

Barton and coworkers exploited this strategy in the preparation of overcrowded ethylenes456 usually the desulfurization of a thiirane is accomplished by one equivalent of tertiary phosphine, mainly triphenylphosphine. However, spontaneous loss of sulfur from thiiranes substituted by aryl or halogen has sporadically been reported. Huisgen has reviewed this subject455 and performed many kinetic studies. He found that the desulfurization step can be accomplished by catalytic thiolates and also by thiobenzophenone or other thioketones, although in this case the reaction is slower (equation 131). [Pg.1447]

As the focus of this review is on copper-dioxygen chemistry, we shall briefly summarize major aspects of the active site chemistry of those proteins involved in 02 processing. The active site structure and chemistry of hemocyanin (He, 02 carrier) and tyrosinase (Tyr, monooxygenase) will be emphasized, since the chemical studies described herein are most relevant to their function. The major classes of these proteins and their origins, primary functions, and leading references are provided in Table 1. Other classes of copper proteins not included here are blue electron carriers [13], copper-thiolate proteins (metallothioneines) [17], and NO reductases (e.g., nitrite [NIR] [18] or nitrous oxide [19]). [Pg.470]


See other pages where Thiolating review is mentioned: [Pg.177]    [Pg.211]    [Pg.1]    [Pg.343]    [Pg.95]    [Pg.1189]    [Pg.371]    [Pg.44]    [Pg.85]    [Pg.36]    [Pg.160]    [Pg.272]    [Pg.75]    [Pg.375]    [Pg.300]    [Pg.834]    [Pg.407]    [Pg.90]    [Pg.218]    [Pg.1032]    [Pg.65]    [Pg.154]    [Pg.160]    [Pg.260]    [Pg.177]    [Pg.801]    [Pg.639]    [Pg.260]    [Pg.233]   
See also in sourсe #XX -- [ Pg.7 , Pg.43 ]




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