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Tris(2-pyridylmethyl)amine
Tris(2-pyridylmethyl)amine (abbreviated TPMA or TPA) is an organic compound with the formula (C5H4NCH2)3N. It is a tertiary amine with three picolyl substituents. It is a white solid that is soluble in polar organic solvents. It is a ligand in coordination chemistry. The ligand is prepared by the alkylation of 2-picolylamine by picolyl chloride:{{cite book , author1=James W. Canary , author2=Yihan Wang , author3=Richard Roy, Jr. , title = Tris 2-Pyridyl)MethylAmine (TPA) and (+)-Bis 2-Pyridyl)methyl1-(2-Pyridyl)-Ethylamine (α-Metpa) , journal = Inorg. Synth. , series=Inorganic Syntheses , year = 1998 , volume = 32 , pages = 70–75 , doi = 10.1002/9780470132630.ch11, isbn=9780470132630 :2 C5H4NCH2Cl + C5H4NCH2NH2 → (C5H4NCH2)3N + 2 HCl TPMA is a tripodal ligand, often used to simulate the coordination environment within some proteins. It is also used as a copper ligand in ATRP. Related ligands * dipicolylamine, an intermediate in the synthesis of TPMA. *2-pi ... [...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 and homogeneous catalysis. Because the ligands are polydentate, they do not readily dissociate from the metal centre. Many tripodal ligands have C3 symmetry. Coordination chemistry In their coordination complexes with an octahedral molecular geometry the tridentate tripod ligands occupy one face, leading to a fixed 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 metal centres, these ligands impose C3 symmetry, which can lead to uncommon ligand field splitting patterns. Tripodal ligands are often able to coordinately saturate metal ions with lower coordination numbers. One tripodal ligand of commercial significance is nitrilotriacetate, N(CH2CO2−)3 because it is cheaply produced and has a high affinity f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipicolylamine
Dipicolylamine is an organic compound with the formula HN(CH2C5H4N)2. It is a yellow liquid that is soluble in polar organic solvents. The molecule is a secondary amine with two picolyl substituents. The compound is a common tridentate ligand in coordination chemistry.Huy Tien Ngo, Xuejian Liu, Katrina A. Jolliffe "Anion recognition and sensing with Zn(II)–dipicolylamine complexes" Chem. Soc. Rev., 2012,41, 4928-4965. {{doi, 10.1039/C2CS35087D The compound can be prepared by many methods, alkylation of picolinylamine with picolinyl chloride, deamination of picolinylamine, and reductive amination of picolinyl amine and pyridine-2-carboxaldehyde. It is commonly used to bind to bacteria in purifying mixtures that require separation. Related compounds * Tris(2-pyridylmethyl)amine Tris(2-pyridylmethyl)amine (abbreviated TPMA or TPA) is an organic compound with the formula (C5H4NCH2)3N. It is a tertiary amine with three picolyl substituents. It is a white solid that is soluble ... [...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. Living t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-picoline
2-Methylpyridine, or 2-picoline, is the compound described with formula C6H7N. 2-Picoline is a colorless liquid that has an unpleasant odor similar to pyridine. It is mainly used to make vinylpyridine and the agrichemical nitrapyrin. Synthesis 2-Picoline was the first pyridine compound reported to be isolated in pure form. It was isolated from coal tar in 1846 by T. Anderson. This chemistry was practiced by Reilly Industries. It is now mainly produced by two principal routes. One method involves the condensation of acetaldehyde and ammonia in the presence of an oxide catalyst. This method affords a mixture of 2- and 4-picolines: : Another method involves the condensation of acetone and acrylonitrile to give 5-oxohexanenitrile, which then cyclizes to give 2-picoline. Approximately 8000 t/a was produced worldwide in 1989. Reactions Most of the reactions of picoline are centered on the methyl group. For example, the principal use of 2-picoline is as a precursor of 2-vinylpyrid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligand
In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electron pairs, often through Lewis bases. The nature of metal–ligand bonding can range from covalent to ionic. Furthermore, the metal–ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known to involve Lewis acidic "ligands". Metals and metalloids are bound to ligands in almost all circumstances, although gaseous "naked" metal ions can be generated in a high vacuum. Ligands in a complex dictate the reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection requires critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environmental chemi ... [...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 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] |
2-Picolylamine
2-Picolylamine is an organic compound with the formula H2NCH2C5H4N. A colorless liquid, it is a common bidentate ligand and a precursor to more complex multidentate ligands such as tris(2-pyridylmethyl)amine. It is usually prepared by hydrogenation of 2-cyanopyridine. One such complex is Baratta's catalyst RuCl2(PPh3)2(ampy) (ampy = 2-picolylamine) for transfer hydrogenation. Salts of the complex e(pyCH2NH2)3sup>2+ exhibit spin crossover behavior, whereby the complex switches from high to low spin configurations, depending on the temperature. Safety The oral in quail Quail is a collective name for several genera of mid-sized birds generally placed in the order Galliformes. The collective noun for a group of quail is a flock, covey, or bevy. Old World quail are placed in the family Phasianidae, and New Wor ... is low, being 750 mg/kg. References {{DEFAULTSORT:Picolylamine, 2- 2-Pyridyl compounds Amines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement. Copper is one of the few metals that can occur in nature in a directly usable metallic form ( native metals). This led to very early human use in several regions, from circa 8000 BC. Thousands of years later, it was the first metal to be smelted from sulfide ores, circa 5000 BC; the first metal to be cast into a shape in a mold, c. 4000 BC; and the first metal to be purposely alloyed with another metal, tin, to create ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atom-transfer Radical-polymerization
Atom transfer radical polymerization (ATRP) is an example of a reversible-deactivation radical polymerization. Like its counterpart, ATRA, or atom transfer radical addition, ATRP is a means of forming a carbon-carbon bond with a transition metal catalyst. Polymerization from this method is called atom transfer radical addition polymerization (ATRAP). As the name implies, the atom transfer step is crucial in the reaction responsible for uniform polymer chain growth. ATRP (or transition metal-mediated living radical polymerization) was independently discovered by Mitsuo Sawamoto and by Krzysztof Matyjaszewski and Jin-Shan Wang in 1995. ::The following scheme presents a typical ATRP reaction: Overview of ATRP ATRP usually employs a transition metal complex as the catalyst with an alkyl halide as the initiator (R-X). Various transition metal complexes, namely those of Cu, Fe, Ru, Ni, and Os, have been employed as catalysts for ATRP. In an ATRP process, the dormant species is activ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amines
In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group (these may respectively be called alkylamines and arylamines; amines in which both types of substituent are attached to one nitrogen atom may be called alkylarylamines). Important amines include amino acids, biogenic amines, trimethylamine, and aniline; Inorganic derivatives of ammonia are also called amines, such as monochloramine (). The substituent is called an amino group. Compounds with a nitrogen atom attached to a carbonyl group, thus having the structure , are called amides and have different chemical properties from amines. Classification of amines Amines can be classified according to the nature and number of substituents on nitrogen. Aliphatic amines contain only H and alkyl substituents. Aromatic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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