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Nadic Anhydride
Nadic anhydride, also known as 5-norbornene-2,3-dicarboxylic anhydride, is an organic acid anhydride derivative of norbornene. Stereochemistry Nadic anhydride exhibits Endo-exo isomerism, ''endo''-''exo'' isomerism. In the ''exo'' isomer, the acid anhydride group points in the same direction towards the bridging carbon of the norbornene, while in the ''endo'' isomer the acid anhydride group points in the opposite direction. These isomers are respectively named ''cis''-5-norbornene-''exo''-2,3-dicarboxylic anhydride (also known as himic anhydride) and ''cis''-5-norbornene-''endo''-2,3-dicarboxylic anhydride (also known as carbic anhydride). Commercially available nadic anhydride is mainly the ''endo'' isomer, as this is the isomer predominantly made in the Diels-Alder reaction in its synthesis. Preparation In the patent for the Diels-Alder reaction, nadic anhydride was given as an example of the reaction, made by the addition of maleic anhydride to cyclopentadiene, which gives mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Acid Anhydride
An organic acid anhydride is an acid anhydride that is an organic compound. An acid anhydride is a compound that has two acyl groups bonded to the same oxygen atom. A common type of organic acid anhydride is a carboxylic anhydride, where the parent acid is a carboxylic acid, the formula of the anhydride being (RC(O))2O. Symmetrical acid anhydrides of this type are named by replacing the word ''acid'' in the name of the parent carboxylic acid by the word ''anhydride''. Thus, (CH3CO)2O is called ''acetic anhydride.'' Mixed (or unsymmetrical) acid anhydrides, such as acetic formic anhydride (see below), are known, whereby reaction occurs between two different carboxylic acids. Nomenclature of unsymmetrical acid anhydrides list the names of both of the reacted carboxylic acids before the word "anhydride" (for example, the dehydration reaction between benzoic acid and propanoic acid would yield "benzoic propanoic anhydride"). One or both acyl groups of an acid anhydride may also be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentadiene
Cyclopentadiene is an organic compound with the formula C5H6.LeRoy H. Scharpen and Victor W. Laurie (1965): "Structure of cyclopentadiene". ''The Journal of Chemical Physics'', volume 43, issue 8, pages 2765-2766. It is often abbreviated CpH because the cyclopentadienyl anion is abbreviated Cp−. This colorless liquid has a strong and unpleasant odor. At room temperature, this cyclic diene dimerizes over the course of hours to give dicyclopentadiene via a Diels–Alder reaction. This dimer can be restored by heating to give the monomer. The compound is mainly used for the production of cyclopentene and its derivatives. It is popularly used as a precursor to the cyclopentadienyl anion (Cp−), an important ligand in cyclopentadienyl complexes in organometallic chemistry. Production and reactions Cyclopentadiene production is usually not distinguished from dicyclopentadiene since they interconvert. They are obtained from coal tar (about 10–20 g/tonne) and by stea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxylic Anhydrides
In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids. Deprotonation of a carboxylic acid gives a carboxylate anion. Examples and nomenclature Carboxylic acids are commonly identified by their trivial names. They at oftentimes have the suffix ''-ic acid''. IUPAC-recommended names also exist; in this system, carboxylic acids have an ''-oic acid'' suffix. For example, butyric acid (C3H7CO2H) is butanoic acid by IUPAC guidelines. For nomenclature of complex molecules containing a carboxylic acid, the carboxyl can be considered position one of the parent chain even if there are other substituents, such as 3-chloropropanoic acid. Alternately, it can be named as a "carboxy" or "carboxylic acid" substituent on another pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angewandte Chemie International Edition
''Angewandte Chemie'' (, meaning "Applied Chemistry") is a weekly peer-reviewed scientific journal that is published by Wiley-VCH on behalf of the German Chemical Society (Gesellschaft Deutscher Chemiker). Publishing formats include feature-length reviews, short highlights, research communications, minireviews, essays, book reviews, meeting reviews, correspondences, corrections, and obituaries. This journal contains review articles covering all aspects of chemistry. According to the '' Journal Citation Reports'', the journal had a 2021 impact factor of 16.823. Editions The journal appears in two editions with separate volume and page numbering: a German edition, ''Angewandte Chemie'' ( (print), (online)), and a fully English-language edition, ''Angewandte Chemie International Edition'' ( (print), (online)). The editions are identical in content with the exception of occasional reviews of German-language books or German translations of IUPAC recommendations. Business mode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiol-ene Reaction
In organosulfur chemistry, the thiol-ene reaction (also alkene hydrothiolation) is an organic reaction between a thiol () and an alkene () to form a thioether (). This reaction was first reported in 1905, but it gained prominence in the late 1990s and early 2000s for its feasibility and wide range of applications. This reaction is accepted as a click chemistry reaction given the reactions’ high yield, stereoselectivity, high rate, and thermodynamic driving force. The reaction results in an anti-Markovnikov addition of a thiol compound to an alkene. Given the stereoselectivity, high rate and yields, this synthetically useful reaction may underpin future applications in material and biomedical sciences. Mechanisms Radical addition Thiol-ene additions are known to proceed through two mechanisms: free-radical additions and catalyzed Michael additions. Free-radical additions can be initiated by light, heat or radical initiators, which form a thiyl radical species. The r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemistry Letters
''Chemistry Letters'' is a peer-reviewed scientific journal published by the Chemical Society of Japan. It specializes in the rapid publication of reviews and letters on all areas of chemistry. The editor-in-chief is Mitsuhiko Shionoya (University of Tokyo). According to the ''Journal Citation Reports'', the journal has a 2014 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as ... of 1.23. References External links * Chemistry journals Publications established in 1972 English-language journals Academic journals published by learned and professional societies Monthly journals Chemical Society of Japan {{chem-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kurt Alder
Kurt Alder (; 10 July 1902 – 20 June 1958) was a German chemist and Nobel laureate. Biography Alder was born in the industrial area of Königshütte, Silesia (modern day Chorzów, Upper Silesia, Poland), where he received his early schooling. Alder left the area when Königshütte became part of Poland in 1922. He studied chemistry at the University of Berlin from 1922, and later at the University of Kiel where his PhD was awarded in 1926 for work supervised by Otto Paul Hermann Diels. In 1930 Alder was appointed reader for chemistry at Kiel, and promoted to lecturer in 1934. In 1936 he left Kiel to join I G Farben Industrie at Leverkusen, where he worked on synthetic rubber. Then in 1940 he was appointed Professor of Experimental Chemistry and Chemical Technology at the University of Cologne and Director of the Institute of Chemistry there. Throughout this time and despite the many obstacles to original research in Europe at the time, he continued a systemati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Diels
Otto Paul Hermann Diels (; 23 January 1876 – 7 March 1954) was a German chemist. His most notable work was done with Kurt Alder on the Diels–Alder reaction, a method for diene synthesis. The pair was awarded the Nobel Prize in Chemistry in 1950 for their work. Their method of synthesizing cyclic organic compounds proved valuable for the manufacture of synthetic rubber and plastic. He completed his education at the University of Berlin, where he later worked. Diels was employed at the University of Kiel when he completed his Nobel Prize–winning work, and remained there until he retired in 1945. Diels was married, with five children. He died in 1954. Early life Diels was born on 23 January 1876 in Hamburg, Germany, and moved with his family to Berlin when he was two years old. He studied in Berlin at Joachimsthalsches Gymnasium before attending the University of Berlin starting in 1895. While at university, Diels studied chemistry under Emil Fischer, eventuall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maleic Anhydride
Maleic anhydride is an organic compound with the formula C2H2(CO)2O. It is the acid anhydride of maleic acid. It is a colorless or white solid with an acrid odor. It is produced industrially on a large scale for applications in coatings and polymers. Production Maleic anhydride is produced by vapor-phase oxidation of ''n''-butane. The overall process converts the methyl groups to carboxylate and dehydrogenates the backbone. The selectivity of the process reflects the robustness of maleic anhydride, with its conjugated double-bond system. Traditionally maleic anhydride was produced by the oxidation of benzene or other aromatic compounds. As of 2006, only a few smaller plants continue to use benzene. In both cases, benzene and butane are fed into a stream of hot air, and the mixture is passed through a catalyst bed at high temperature. The ratio of air to hydrocarbon is controlled to prevent the mixture from igniting. Vanadium pentoxide and molybdenum trioxide are the catal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norbornene
Norbornene or norbornylene or norcamphene is a highly strained bridged cyclic hydrocarbon. It is a white solid with a pungent sour odor. The molecule consists of a cyclohexene ring with a methylene bridge between carbons 1 and 4. The molecule carries a double bond which induces significant ring strain and significant reactivity. Production Norbornene is made by a Diels–Alder reaction of cyclopentadiene and ethylene. Many substituted norbornenes can be prepared similarly. Related bicyclic compounds are norbornadiene, which has the same carbon skeleton but with two double bonds, and norbornane which is prepared by hydrogenation of norbornene. Reactions Norbornene undergoes an acid-catalyzed hydration reaction to form norborneol. This reaction was of great interest in the elucidation of the non-classical carbonion controversy. Norbornene is used in the Catellani reaction and in norbornene-mediated ''meta''-C−H activation. Certain substituted norbornenes undergo unus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
