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Tetraphenylmethane
Tetraphenylmethane is an organic compound consisting of a methane core with four phenyl substituents. It was first synthesized by Moses Gomberg in 1898. Synthesis Gomberg's classical organic synthesis shown below starts by reacting triphenylmethyl bromide 1 with phenylhydrazine 2 to the hydrazine 3. Oxidation with nitrous acid then produces the azo compound 4 from which on heating above the melting point, nitrogen gas evolves with formation of tetraphenylmethane 5.{{cite journal , title = On tetraphenylmethane , first= M. , last=Gomberg , journal = J. Am. Chem. Soc. , year = 1898 , volume = 20 , issue = 10 , pages = 773–780 , doi= 10.1021/ja02072a009, url= https://zenodo.org/record/1428930 : Gomberg was able to distinguish this compound from triphenylmethane ( elemental analysis was not an option given the small differences in the hydrogen fractions of 6.29% and 6.60%) by nitration of 5 with nitric acid to 6. A strong base would be able to abstract th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetraphenylmethane Full
Tetraphenylmethane is an organic compound consisting of a methane core with four phenyl substituents. It was first synthesized by Moses Gomberg in 1898. Synthesis Gomberg's classical organic synthesis shown below starts by reacting triphenylmethyl bromide 1 with phenylhydrazine 2 to the hydrazine 3. Oxidation with nitrous acid then produces the azo compound 4 from which on heating above the melting point, nitrogen gas evolves with formation of tetraphenylmethane 5.{{cite journal , title = On tetraphenylmethane , first= M. , last=Gomberg , journal = J. Am. Chem. Soc. , year = 1898 , volume = 20 , issue = 10 , pages = 773–780 , doi= 10.1021/ja02072a009, url= https://zenodo.org/record/1428930 : Gomberg was able to distinguish this compound from triphenylmethane (elemental analysis was not an option given the small differences in the hydrogen fractions of 6.29% and 6.60%) by nitration of 5 with nitric acid to 6. A strong base would be able to abstract the methine proto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moses Gomberg
Moses Gomberg (February 8, 1866 – February 12, 1947) was a chemistry professor at the University of Michigan. He was elected to the National Academy of Sciences and served as president of the American Chemical Society. Early life and education He was born in Yelisavetgrad, Russian Empire to a Jewish merchant family. His father was Hershko (Hirsh) Gomberg and his mother was Maryam-Ethel Reznikova. In 1884, the family emigrated to Chicago to escape the pogroms following the assassination of Czar Alexander II. In Chicago he worked at the Stock Yards while attending Lake High School. In 1886, Moses entered the University of Michigan, where he obtained his B.Sc. in 1890 and his doctorate in 1894 under the supervision of A. B. Prescott. His thesis, titled "''Trimethylxanthine and Some of its Derivatives''", dealt with the derivatization of caffeine. Career Appointed an instructor in 1893, Gomberg worked at the University of Michigan for the duration of his professional academic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylmethane
Triphenylmethane, or triphenyl methane, is the hydrocarbon with the formula (C6H5)3CH. This colorless solid is soluble in nonpolar organic solvents and not in water. Triphenylmethane is the basic skeleton of many synthetic dyes called triarylmethane dyes, many of them are pH indicators, and some display fluorescence. A trityl group in organic chemistry is a triphenylmethyl group Ph3C, e.g. triphenylmethyl chloride (trityl chloride) and the triphenylmethyl radical (trityl radical). Preparation Triphenylmethane was first synthesized in 1872 by the German chemist August Kekulé and his Belgian student Antoine Paul Nicolas Franchimont (1844–1919) by heating diphenylmercury (Hg(C6H5)2, ''Quecksilberdiphenyl'') with benzal chloride (C6H5CHCl2, ''Benzylenchlorid''). Triphenylmethane can be synthesized by Friedel–Crafts reaction from benzene and chloroform with aluminium chloride catalyst: :3 C6H6 + CHCl3 → Ph3CH + 3 HCl Alternatively, benzene may react with carbon tetr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexaphenylethane
Hexaphenylethane is a hypothetical organic compound consisting of an ethane core with six phenyl substituents. All attempts at its synthesis have been unsuccessful. The trityl free radical, Ph3C, was originally thought to dimerize to form hexaphenylethane. However, an inspection of the NMR spectrum of this dimer reveals that it is in fact a non-symmetrical species, Gomberg's dimer instead. A substituted derivative of hexaphenylethane, hexakis(3,5-di-''t''-butylphenyl)ethane, has however been prepared. It features a very long central C–C bond at 167 pm (compared to the typical bond length of 154 pm). Attractive London dispersion forces between the ''t''-butyl substituents are believed to be responsible for the stability of this very hindered molecule. See also * Tetraphenylmethane Tetraphenylmethane is an organic compound consisting of a methane core with four phenyl substituents. It was first synthesized by Moses Gomberg in 1898. Synthesis Gomberg's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylmethane
Triphenylmethane, or triphenyl methane, is the hydrocarbon with the formula (C6H5)3CH. This colorless solid is soluble in nonpolar organic solvents and not in water. Triphenylmethane is the basic skeleton of many synthetic dyes called triarylmethane dyes, many of them are pH indicators, and some display fluorescence. A trityl group in organic chemistry is a triphenylmethyl group Ph3C, e.g. triphenylmethyl chloride (trityl chloride) and the triphenylmethyl radical (trityl radical). Preparation Triphenylmethane was first synthesized in 1872 by the German chemist August Kekulé and his Belgian student Antoine Paul Nicolas Franchimont (1844–1919) by heating diphenylmercury (Hg(C6H5)2, ''Quecksilberdiphenyl'') with benzal chloride (C6H5CHCl2, ''Benzylenchlorid''). Triphenylmethane can be synthesized by Friedel–Crafts reaction from benzene and chloroform with aluminium chloride catalyst: :3 C6H6 + CHCl3 → Ph3CH + 3 HCl Alternatively, benzene may react with carbon tetr ... [...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] |
Base (chemistry)
In chemistry, there are three definitions in common use of the word base, known as Arrhenius bases, Brønsted bases, and Lewis bases. All definitions agree that bases are substances that react with acids, as originally proposed by G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form Hydroxide ions OH−. These ions can react with hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction. A base was therefore a metal hydroxide such as NaOH or Ca(OH)2. Such aqueous hydroxide solutions were also described by certain characteristic properties. They are slippery to the touch, can taste bitter and change the color of pH indicators (e.g., turn red litmus paper blue). In water, by altering the autoionization equilibrium, bases yield solutions in which the hydrogen ion activity is lower than it is in pure water, i.e., the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toluene
Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) attached to a phenyl group. As such, its systematic IUPAC name is methylbenzene. Toluene is predominantly used as an industrial feedstock and a solvent. As the solvent in some types of paint thinner, permanent markers, contact cement and certain types of glue, toluene is sometimes used as a recreational inhalant and has the potential of causing severe neurological harm. History The compound was first isolated in 1837 through a distillation of pine oil by the Polish chemist Filip Walter, who named it ''rétinnaphte''. In 1841, French chemist Henri Étienne Sainte-Claire Deville isolated a hydrocarbon from balsam of Tolu (an aromatic extract from the tropical Colombian tree '' Myroxylon balsamum''), which Deville recognized as simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylmethyl Radical
The triphenylmethyl radical (often shorted to trityl radical) is an organic compound with the formula (C6H5)3C. It is a persistent radical. It was the first radical ever to be described in organic chemistry. Because of its accessibility, the trityl radical has been heavily exploited. Preparation and properties It can be prepared by homolysis of triphenylmethyl chloride 1 by a metal like silver or zinc in benzene or diethyl ether. The radical 2 forms a chemical equilibrium with the quinoid-type dimer 3 (Gomberg's dimer). In benzene the concentration of the radical is 2%. Solutions containing the radical are yellow; when the temperature of the solution is raised, the yellow color becomes more intense as the equilibrium is shifted in favor of the radical (in accordance with Le Chatelier's principle). When exposed to air, the radical rapidly oxidizes to the peroxide, and the color of the solution changes from yellow to colorless. Likewise, the radical reacts with iodine to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pararosaniline
Pararosaniline, Basic Red 9, or C.I. 42500 is an organic compound with the formula H2NC6H4)3Cl. It is a magenta solid with a variety of uses as a dye. It is one of the four components of basic fuchsine. (The others are rosaniline, new fuchsine and magenta II.) It is structurally related to other triarylmethane dyes called methyl violets including crystal violet, which feature methyl groups on nitrogen. It is prepared by the condensation of aniline and para-aminobenzaldehyde. Alternatively, it arises from the oxidation of 4,4'-bis(aminophenyl)methane in the presence of aniline. Uses *It is used to dye polyacrylonitrile fibers. *Pararosaniline is used as a colorimetric test for aldehydes, in the Schiff test. It is the only basic fuchsine component suitable for making the aldehyde-fuchsine stain for pancreatic islet beta cells. *It has use as an Antischistosomal. Related compounds * 4,4'-Thiodianiline * 4,4'-Methylenedianiline * 4,4'-Oxydianiline * Dapsone Dapsone, als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aniline
Aniline is an organic compound with the formula C6 H5 NH2. Consisting of a phenyl group attached to an amino group, aniline is the simplest aromatic amine. It is an industrially significant commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans. Relative to benzene, it is electron-rich. It thus participates more rapidly in electrophilic aromatic substitution reactions. Likewise, it is also prone to oxidation: while freshly purified aniline is an almost colorless oil, exposure to air results in gradual darkening to yellow or red, due to the formation of strongly colored, oxidized impurities. Aniline can be diazotized to give a diazonium salt, which can then undergo vario ... [...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. 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 for producing hydrochloric acid, as perhaps manifested in the following recipe from his ("The Book of Secrets"): However, it appears that in most of his experiments al-Razi disregarded the gaseous products, concentrating instead on the color c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
