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Phenyllithium
Phenyllithium or lithobenzene is an organometallic agent with the empirical formula C6H5Li. It is most commonly used as a metalating agent in organic syntheses and a substitute for Grignard reagents for introducing phenyl groups in organic syntheses. Crystalline phenyllithium is colorless; however, solutions of phenyllithium are various shades of brown or red depending on the solvent used and the impurities present in the solute. Preparation Phenyllithium was first produced by the reaction of lithium metal with diphenylmercury: :(C6Η5)2Ηg + 2Li → 2C6Η5Li + Ηg Reaction of a phenyl halide with lithium metal produces phenyllithium: :X-Ph + 2Li → Ph-Li + LiX Phenyllithium can also be synthesized with a metal-halogen exchange reaction: :n-BuLi + X-Ph → n-BuX + Ph-Li The predominant method of producing phenyllithium today are the latter two syntheses. Reactions The primary use of PhLi is to facilitate formation of carbon-carbon bonds by nucleophilic addition and substitut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organolithium
In organometallic chemistry, organolithium reagents are chemical compounds that contain carbon–lithium (C–Li) bonds. These reagents are important in organic synthesis, and are frequently used to transfer the organic group or the lithium atom to the substrates in synthetic steps, through nucleophilic addition or simple deprotonation. Organolithium reagents are used in industry as an initiator for anionic polymerization, which leads to the production of various elastomers. They have also been applied in asymmetric synthesis in the pharmaceutical industry. Due to the large difference in electronegativity between the carbon atom and the lithium atom, the C−Li bond is highly ionic. Owing to the polar nature of the C−Li bond, organolithium reagents are good nucleophiles and strong bases. For laboratory organic synthesis, many organolithium reagents are commercially available in solution form. These reagents are highly reactive, and are sometimes pyrophoric. History and de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organolithium Compounds
In organometallic chemistry, organolithium reagents are chemical compounds that contain carbon–lithium (C–Li) bonds. These reagents are important in organic synthesis, and are frequently used to transfer the organic group or the lithium atom to the substrates in synthetic steps, through nucleophilic addition or simple deprotonation. Organolithium reagents are used in industry as an initiator for anionic polymerization, which leads to the production of various elastomers. They have also been applied in asymmetric synthesis in the pharmaceutical industry. Due to the large difference in electronegativity between the carbon atom and the lithium atom, the C−Li bond is highly ionic. Owing to the polar nature of the C−Li bond, organolithium reagents are good nucleophiles and strong bases. For laboratory organic synthesis, many organolithium reagents are commercially available in solution form. These reagents are highly reactive, and are sometimes pyrophoric. History and dev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylsodium
Phenylsodium C6H5Na is an organosodium compound. Solid phenylsodium was first isolated by Nef in 1903. Although the behavior of phenylsodium and phenyl magnesium bromide are similar, the organosodium compound is very rarely used. Synthesis The existence of phenylsodium was originally proposed by August Kekulé after observing the formation of sodium benzoate in the reaction of bromobenzene with sodium under carbon dioxide. Transmetalation In the original synthesis, diphenylmercury and sodium was shown to yield a suspension of phenylsodium: :(C6H5)2Hg + 3 Na → 2 C6H5Na + NaHg The Shorigen reaction is also used in the generation of phenylsodium, where an alkyl sodium compound is treated with benzene: : RNa + C6H6 → RH + C6H5Na The method can also result in the addition of a second sodium. This dimetallation occurs in the ''meta'' and ''para'' positions. The use of certain alkyl sodium compounds such as n-amyl sodium is known to greatly increase this dimetallation effect. Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylcopper
Phenylcopper is an organometallic chemical compound of copper. Its chemical formula is . Synthesis Phenylcopper was the first known organocopper compound and was first prepared in 1923 from phenylmagnesium iodide and copper(I) iodide and in 1936 by Henry Gilman by transmetallation of phenylmagnesium iodide with copper(I) chloride. Phenylcopper can be obtained by reacting phenyl lithium with copper(I) bromide in diethyl ether. :\mathrm Properties Phenylcopper is a colorless solid substance that is soluble in pyridine. It can be stored for a few days without decomposition under nitrogen or in vacuum. Rapid decomposition takes place in air. Water decomposes phenylcopper to form red copper (I) oxide and varying amounts of benzene and biphenyl. It forms stable complexes with tributylphosphine and triphenylphosphine. When dissolved in dimethyl sulfide, phenylcopper forms dimers and trimers (aggregates of two or three molecules). Related A diphenylcuprate(I) ion exists that can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organometallic
Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali, alkaline earth, and transition metals, and sometimes broadened to include metalloids like boron, silicon, and selenium, as well. Aside from bonds to organyl fragments or molecules, bonds to 'inorganic' carbon, like carbon monoxide (metal carbonyls), cyanide, or carbide, are generally considered to be organometallic as well. Some related compounds such as transition metal hydrides and metal phosphine complexes are often included in discussions of organometallic compounds, though strictly speaking, they are not necessarily organometallic. The related but distinct term " metalorganic compound" refers to metal-containing compounds lacking direct metal-carbon bonds but which contain organic ligands. Metal β-diketonates, alkoxides, dialkylamides, and metal phosphine complexes are r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grignard Reagents
A Grignard reagent or Grignard compound is a chemical compound with the general formula , where X is a halogen and R is an organic group, normally an alkyl or aryl. Two typical examples are methylmagnesium chloride and phenylmagnesium bromide . They are a subclass of the organomagnesium compounds. Grignard compounds are popular reagents in organic synthesis for creating new carbon-carbon bonds. For example, when reacted with another halogenated compound in the presence of a suitable catalyst, they typically yield and the magnesium halide as a byproduct; and the latter is insoluble in the solvents normally used. In this aspect, they are similar to organolithium reagents. Pure Grignard reagents are extremely reactive solids. They are normally handled as solutions in solvents such as diethyl ether or tetrahydrofuran; which are relatively stable as long as water is excluded. In such a medium, a Grignard reagent is invariably present as a complex with the magnesium atom con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of The American Chemical Society
The ''Journal of the American Chemical Society'' is a weekly peer-reviewed scientific journal that was established in 1879 by the American Chemical Society. The journal has absorbed two other publications in its history, the ''Journal of Analytical and Applied Chemistry'' (July 1893) and the ''American Chemical Journal'' (January 1914). It covers all fields of chemistry. Since 2021, the editor-in-chief is Erick M. Carreira ( ETH Zurich). In 2014, the journal moved to a hybrid open access publishing model. Abstracting and indexing The journal is abstracted and indexed in Chemical Abstracts Service, Scopus, EBSCO databases, ProQuest databases, Index Medicus/MEDLINE/PubMed, and the Science Citation Index Expanded. According to the ''Journal Citation Reports'', the journal has a 2021 impact factor of 16.383. Editors-in-chief The following people are or have been editor-in-chief: * 1879–1880 – Hermann Endemann * 1880–1881 – Gideon E. Moore * 1881–1882 – Hermann End ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphenylmercury
Diphenylmercury is the organomercury compound with the formula Hg(C6H5)2. It is a white solid. The compound is of historic interest as a particularly stable organometallic compound but it finds few uses because of its high toxicity. Preparation Commercially available, this compound can be prepared by several routes. It results from treating phenylmercury acetate with sodium stannite, by the reaction of mercuric halides with phenylmagnesium bromide, and the reaction of bromobenzene with sodium amalgam Sodium amalgam, commonly denoted Na(Hg), is an alloy of mercury and sodium. The term amalgam is used for alloys, intermetallic compounds, and solutions (both solid solutions and liquid solutions) involving mercury as a major component. Sodium am .... Safety Diphenylmercury is highly toxic. References {{Mercury compounds Organomercury compounds Phenyl compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Phenylpyridine
2-Phenylpyridine is an organic compound with the formula C6H5C5H4N (or C11H9N). It is a colourless viscous liquid. The compound and related derivatives have attracted interest as precursors to highly fluorescent metal complexes of possible value as organic light emitting diodes (OLEDs). The compound is prepared by the reaction of phenyl lithium Phenyllithium or lithobenzene is an organometallic agent with the empirical formula C6H5Li. It is most commonly used as a metalating agent in organic syntheses and a substitute for Grignard reagents for introducing phenyl groups in organic synth ... with pyridine: :C6H5Li + C5H5N → C6H5-C5H4N + LiH The reaction of iridium trichloride with 2-phenylpyridine proceeds via cyclometallation to give the chloride-bridged complex: :4 C6H5-C5H4N + 2 IrCl3(H2O)3 → Ir2Cl2(C6H4-C5H4N)4 + 4 HCl This complex can be converted to the pictured tris(cyclometallated) derivative tris(2-phenylpyridine)iridium. References Further reading * {{D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arene Substitution Pattern
Arene substitution patterns are part of organic chemistry IUPAC nomenclature and pinpoint the position of substituents other than hydrogen in relation to each other on an aromatic hydrocarbon. ''Ortho'', ''meta'', and ''para'' substitution * In ''ortho''-substitution, two substituents occupy positions next to each other, which may be numbered 1 and 2. In the diagram, these positions are marked R and ''ortho''. * In ''meta''-substitution the substituents occupy positions 1 and 3 (corresponding to R and ''meta'' in the diagram). * In ''para''-substitution, the substituents occupy the opposite ends (positions 1 and 4, corresponding to R and ''para'' in the diagram). The toluidines serve as an example for these three types of substitution. Synthesis Electron donating groups, for example amino, hydroxyl, alkyl, and phenyl groups tend to be ''ortho''/''para''-directors, and electron withdrawing groups such as nitro, nitrile, and ketone groups, tend to be ''meta''-directors. Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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