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Cis,cis-1,3,5-triaminocyclohexane
''cis'',''cis''-1,3,5-Triaminocyclohexane is an organic compound with the formula (CH2CHNH2)3. It is a triamine. Of the many isomers possible for triaminocyclohexane, the ''cis'',''cis''-1,3,5-derivative has attracted attention because it is a common tripodal ligand, abbreviated as tach. It is a colorless oil. It is a popular tridentate ligand in coordination chemistry. It is prepared from the triscarbamate of cyclohexane. The latter is generated via the Curtius rearrangement starting from cyclohexanetricarboxylic acid. Related ligands *Tris(aminomethyl)ethane 1,1,1-Tris(aminomethyl)ethane (TAME) is an organic compound with the formula CHC(CHNH). It is a colorless liquid. It is classified as a polyamine tripodal ligand, i.e., capable of binding to metal ions through three sites and hence is a tridentate ..., another tripodal triamine (CH3C(CH2NH2]3) References {{DEFAULTSORT:Triaminocyclohexane, cis,cis-1,3,5- Tripodal ligands Polyamines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tripodal Ligand
Tripodal ligands are tri- and tetradentate ligands. They are popular in research in the areas of coordination chemistry 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 chemical bond, bound molecules or ions, that are in turn known as ''ligands'' or complexing ... and homogeneous catalysis. Because the ligands are polydentate, they do not readily dissociate from the metal centre. Many tripodal ligands have C3 symmetry group, symmetry. Coordination chemistry In their coordination complexes with an octahedral molecular geometry the tridentate tripod ligands occupy one face, leading to a fixed Coordination complexes#Cis–trans isomerism and facial–meridional isomerism, facial (or ''fac'') geometry. The tetradentate tripodal ligands occupy four contiguous sites, leaving two ''cis'' positions available on the octahedral metal center. When bound to four- and five-coordinate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon- hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Livin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triamine
A polyamine is an organic compound having more than two amino groups. Alkyl polyamines occur naturally, but some are synthetic. Alkylpolyamines are colorless, hygroscopic, and water soluble. Near neutral pH, they exist as the ammonium derivatives. Most aromatic polyamines are crystalline solids at room temperature. Natural polyamines Low-molecular-weight linear polyamines are found in all forms of life. The principal examples are the triamine spermidine and the tetraamine spermine. They are structurally and biosynthetically related to the diamines putrescine and cadaverine. Polyamine metabolism is regulated by the activity of the enzyme ornithine decarboxylase (ODC). Polyamines are found in high concentrations in the mammalian brain. File:Spermidine-2D-skeletal.svg, spermidine File:Spermine.svg, spermine Synthetic polyamines Several synthetic polyamines are used in chemical industry and the research laboratory. They are mainly of interest as additives to motor oil a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Chemistry
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 chemical bond, bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing chemical compound, compounds, especially those that include transition metals (elements like titanium that belong to the Block (periodic table), 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 Ligand#Polydentate and polyhapto ligand motifs and nomenclature, polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbamate
In organic chemistry, a carbamate is a category of organic compounds with the general formula and structure , which are formally derived from carbamic acid (). The term includes organic compounds (e.g., the ester ethyl carbamate), formally obtained by replacing one or more of the hydrogen atoms by other organic functional groups; as well as salts with the carbamate anion (e.g. ammonium carbamate). Polymers whose units are joined by carbamate groups are an important family of plastics, the polyurethanes. Properties While carbamic acids are unstable, many carbamate esters or ionic) are stable and well known. Equilibrium with carbonate and bicarbonate In water solutions, the carbamate anion slowly equilibrates with the ammonium cation and the carbonate or bicarbonate anions: : : Calcium carbamate is soluble in water, whereas calcium carbonate is not. Adding a calcium salt to an ammonium carbamate/carbonate solution will precipitate some calcium carbonat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curtius Rearrangement
The Curtius rearrangement (or Curtius reaction or Curtius degradation), first defined by Theodor Curtius in 1885, is the thermal decomposition of an acyl azide to an isocyanate with loss of nitrogen gas. The isocyanate then undergoes attack by a variety of nucleophiles such as water, alcohols and amines, to yield a primary amine, carbamate or urea derivative respectively. Several reviews have been published. Preparation of acyl azide The acyl azide is usually made from the reaction of acid chlorides or anydrides with sodium azide or trimethylsilyl azide. Acyl azides are also obtained from treating acylhydrazines with nitrous acid. Alternatively, the acyl azide can be formed by the direct reaction of a carboxylic acid with diphenylphosphoryl azide (DPPA). Reaction mechanism It was believed that the Curtius rearrangement was a two-step processes, with the loss of nitrogen gas forming an acyl nitrene, followed by migration of the R-group to give the isocyanate. However, re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tris(aminomethyl)ethane
1,1,1-Tris(aminomethyl)ethane (TAME) is an organic compound with the formula CHC(CHNH). It is a colorless liquid. It is classified as a polyamine tripodal ligand, i.e., capable of binding to metal ions through three sites and hence is a tridentate chelating ligand, occupying a face of the coordination polyhedron. Preparation TAME is synthesized by the Pd/C-catalyzed hydrogenation of 1,1,1-tris(azidomethyl)ethane. Although azides are potentially explosive, they are excellent and practical source of primary amines. The required tris(azidomethyl)ethane is obtained from the tritosylate by salt metathesis using sodium azide. These two steps are: :3 NaN + CHC(CHOTs) → CHC(CHN) + 3 NaOTs :3 H + CHC(CHN) → CHC(CHNH) + 3 N Complexes of TAME The tripodal TAME ligand coordinates facially to metal ions. This stereochemical feature has been exploited in the preparation of platinum(IV) cage complexes, e.g., t(tame) which is a six coordinate Pt(IV) complex. Platinum in i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
