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Transition Metal Thioether Complex
Transition metal thioether complexes comprise coordination complexes of thioether (R2S) ligands. The inventory is extensive. Dimethylsulfide complexes As the simplest thioether, dimethyl sulfide forms complexes that are illustrative of the class. Well characterized derivatives include ''cis''- iCl4L2 VCl3L2, NbCl5L, NbCl4L2, Cr(CO)5L, CrCl3L3, RuCl2L4, RuCl3L3, RhCl3L3, ''cis''- and ''trans''- rCl4L3, ''cis''-MCl2L2 (M = Pd, Pt), tCl3Lsup>−, ''cis''- and ''trans''- tCl4L2(L = SMe2). With respect to donor properties, dimethyl sulfide is a soft ligand with donor properties weaker than phosphine ligands. Such complexes are generally prepared by treating the metal halide with the thioether. Chloro(dimethyl sulfide)gold(I) can however be prepared by redox reaction of elemental gold and DMSO in the presence of hydrochloric acid. Stereochemistry Thioether complexes feature pyramidal sulfur centers. Typical C-S-C angles are near 99° in both free thioethers and their complexe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Complex
A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing compounds, especially those that include transition metals (elements like titanium that belong to the Periodic Table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom through several of the ligand's atoms; ligands with 2, 3, 4 or even 6 bonds to the central atom are common. These compl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethyl Sulfide
Dimethyl sulfide (DMS) or methylthiomethane is an organosulfur compound with the formula (CH3)2S. Dimethyl sulfide is a flammable liquid that boils at and has a characteristic disagreeable odor. It is a component of the smell produced from cooking of certain vegetables, notably maize, cabbage, beetroot, and seafoods. It is also an indication of bacterial contamination in malt production and brewing. It is a breakdown product of dimethylsulfoniopropionate (DMSP), and is also produced by the bacterial metabolism of methanethiol. Occurrence and production DMS originates primarily from DMSP, a major secondary metabolite in some marine algae. DMS is the most abundant biological sulfur compound emitted to the atmosphere. Emission occurs over the oceans by phytoplankton. DMS is also produced naturally by bacterial transformation of dimethyl sulfoxide (DMSO) waste that is disposed of into sewers, where it can cause environmental odor problems. DMS is oxidized in the marine atmos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloro(dimethyl Sulfide)gold(I)
Chloro(dimethyl sulfide)gold(I) is a coordination complex of gold. It is a white solid. This compound is a common entry point into gold chemistry. Structure As for many other gold(I) complexes, the compound adopts a nearly linear (176.9°) geometry about the central gold atom. The Au-S bond distance is 2.271(2) Å, which is similar to other gold(I)-sulfur bonds. Preparation Chloro(dimethyl sulfide)gold(I) is commercially available. It may be prepared by dissolving gold in aqua regia (to give chloroauric acid), followed by addition of dimethyl sulfide. Alternatively, sodium tetrachloroaurate Sodium tetrachloroaurate is an inorganic compound with the chemical formula NaAuCl4. It is composed of the ions Na+ and AuCl4−. It exists in the anhydrous and dihydrate states. At room temperature, it exists as a golden-orange solid. The anhydr ... may be used as the source of gold(III). The bromo analog, Me2SAuBr, has also been synthesized by a similar route. An approximate equation i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrochloric Acid
Hydrochloric acid, also known as muriatic acid, is an aqueous solution of hydrogen chloride. It is a colorless solution with a distinctive pungent smell. It is classified as a strong acid Acid strength is the tendency of an acid, symbolised by the chemical formula HA, to dissociate into a proton, H+, and an anion, A-. The dissociation of a strong acid in solution is effectively complete, except in its most concentrated solutions .... It is a component of the gastric acid in the digestive systems of most animal species, including humans. Hydrochloric acid is an important laboratory reagent and industrial chemical. History In the early tenth century, the Persian physician and alchemist Abu Bakr al-Razi ( 865–925, Latin: Rhazes) conducted experiments with sal ammoniac (ammonium chloride) and vitriol (hydrated sulfates of various metals), which he distilled together, thus producing the gas hydrogen chloride. In doing so, al-Razi may have stumbled upon a primitive method ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prochiral
In stereochemistry, prochiral molecules are those that can be converted from achiral to chiral in a single step. An achiral species which can be converted to a chiral in two steps is called proprochiral. If two identical substituents are attached to a sp3-hybridized atom, the descriptors ''pro''-R and ''pro''-S are used to distinguish between the two. Promoting the ''pro''-R substituent to higher priority than the other identical substituent results in an ''R'' chirality center at the original sp3-hybridized atom, and analogously for the ''pro''-S substituent. A trigonal planar sp2-hybridized atom can be converted to a chiral center when a substituent is added to the ''re'' or ''si'' () face of the molecule. A face is labeled ''re'' if, when looking at that face, the substituents at the trigonal atom are arranged in increasing Cahn-Ingold-Prelog priority order (1 to 2 to 3) in a clockwise order, and ''si'' if the priorities increase in anti-clockwise order; note that the desi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nb2Cl6(SMe2)3
Niobium(III) chloride also known as niobium trichloride is a compound of niobium and chlorine. The binary phase NbCl3 is not well characterized but many adducts are known. Synthesis left, 184px, Structure of NbCl3(dimethoxyethane)(3-hexyne). Nb3Cl8 is produced by reduction of niobium(V) chloride with hydrogen, or just by heating. Salt-free reduction of dimethoxyethane solution of NbCl5 with 1,4-disilyl-cyclohexadiene in the presence of 3-hexyne produces the coordination complex NbCl3(dimethoxyethane)(3-hexyne): : NbCl5 + C6H6(SiMe3)2 + C2Et2 + dme → NbCl3(dme)(C2Et2) + C6H6 + 2 Me3SiCl An impure dimethoxyethane (dme) adduct of niobium trichloride was produced by reduction of a dme solution of niobium pentachloride with tributyltin hydride: :NbCl5 + 2 Bu3SnH + MeOCH2CH2OMe → NbCl3(MeOCH2CH2OMe) + 2 Bu3SnCl Structure Nb3Cl8 has a hexagonal close packed array of chloride ions. Triangles of niobium occur in octahedral spaces in the chloride array ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DTCO
1,5-Dithiacyclooctane (DTCO) is an organosulfur compound with the formula (CHCH)CHS). This cyclic dithioether is a colorless oil that is soluble in polar solvents. It forms a variety of transition metal thioether complexes. DTO can be oxidized to the bicyclic dication. DTCO was first prepared in 4% yield by dialkylation of 1,3-propanedithiol 1,3-Propanedithiol is the chemical compound with the formula HSCH2CH2CH2SH. This dithiol is a useful reagent in organic synthesis. This liquid, which is readily available commercially, has an intense stench. Use in organic synthesis 1,3-Propan ... with 1,3-dibromopropane. References {{DEFAULTSORT:Dithiacyclooctane, 1, 5- Thioethers Chelating agents Sulfur heterocycles Heterocyclic compounds with 1 ring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crown Ether
In organic chemistry, crown ethers are cyclic chemical compounds that consist of a ring containing several ether groups (). The most common crown ethers are cyclic oligomers of ethylene oxide, the repeating unit being ethyleneoxy, i.e., . Important members of this series are the tetramer (''n'' = 4), the pentamer (''n'' = 5), and the hexamer (''n'' = 6). The term "crown" refers to the resemblance between the structure of a crown ether bound to a cation, and a crown sitting on a person's head. The first number in a crown ether's name refers to the number of atoms in the cycle, and the second number refers to the number of those atoms that are oxygen. Crown ethers are much broader than the oligomers of ethylene oxide; an important group are derived from catechol. Crown ethers strongly bind certain cations, forming complexes. The oxygen atoms are well situated to coordinate with a cation located at the interior of the ring, whereas the exterior of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
9-ane-S3
1,4,7-Trithiacyclononane, also called 9-ane-S3, is the thia-crown ether with the formula (CH2CH2S)3. This cyclic thioether is most often encountered as a tridentate ligand in coordination chemistry, where it forms transition metal thioether complexes. 9-ane-S3 forms complexes with many metal ions, including those considered hard, such as copper(II) and iron(II). Most of its complexes have the formula (9-ane-S3)2sup>2+ and are octahedral. The point group of (9-ane-S3)2sup>2+ is S6. Synthesis This compound was first reported in 1977, and the current synthesis entails the assembly within the coordination sphere of a metal ion followed by decomplexation In chemistry, decomplexation refers to the removal of a ligand from a coordination complex. Decomplexation is of particular interest when the ligand has been synthesized within the coordination sphere of the metal, as is often the case in organomet ...: : References {{DEFAULTSORT:Trithiacyclononane, 1,4,7- Chelating agents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methionine
Methionine (symbol Met or M) () is an essential amino acid in humans. As the precursor of other amino acids such as cysteine and taurine, versatile compounds such as SAM-e, and the important antioxidant glutathione, methionine plays a critical role in the metabolism and health of many species, including humans. It is encoded by the codon AUG. Methionine is also an important part of angiogenesis, the growth of new blood vessels. Supplementation may benefit those suffering from copper poisoning. Overconsumption of methionine, the methyl group donor in DNA methylation, is related to cancer growth in a number of studies. Methionine was first isolated in 1921 by John Howard Mueller. Biochemical details Methionine (abbreviated as Met or M; encoded by the codon AUG) is an α-amino acid that is used in the biosynthesis of proteins. It contains a carboxyl group (which is in the deprotonated −COO− form under biological pH conditions), an amino group (which is in the protonated fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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