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4,7-dihydroisoindole
4,7-Dihydroisoindole in heterocyclic chemistry is a reduced form of isoindole. 4,7-Dihydroisoindole is a useful building block for extended porphyrins which are relevant as materials for optical applications. Synthesis An early attempt to access 4,7-dihydroisoindole — the closest relative of thermodynamically unstable isoindole was performed 1985. It was based on the classical Paal-Knorr synthesis under conditions which probably harmed the electron-rich pyrrole ring. Observed instability of 4,7-dihydroisoindole led researchers to conclude that it was not a useful intermediate in the porphyrin chemistry. It turned out that changing the conditions made it possible to isolate 4,7-dihydroisoindole. Three-step synthesis starting from tosylacetylene which includes Diels-Alder reaction, Barton-Zard synthesis and thermal decarboxylation was reported. Properties Though it was expected that under acidic or basic conditions the migration of double bond in 4,7-dihydroisoindole would happe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoindole
In organic chemistry and heterocyclic chemistry, isoindole consists of a benzene ring fused with pyrrole. The compound is an isomer of indole. Its reduced form is isoindoline. The parent isoindole is a rarely encountered in the technical literature, but substituted derivatives are useful commercially and occur naturally. Isoindoles units occur in phthalocyanines, an important family of dyes. Some alkaloids containing isoindole have been isolated and characterized.Heugebaert, Thomas S. A.; Roman, Bart I.; Stevens, Christian V. "Synthesis of isoindoles and related iso-condensed heteroaromatic pyrroles" Chemical Society Reviews 2012, volume 41, pp. 5626-5640. Synthesis The parent isoindole was prepared by flash vacuum pyrolysis of an N-substituted isoindoline. N-Substituted isoindoles, which are easier to handle, can be prepared by dehydration of isoindoline-N-oxides. They also arise by myriad other methods, e.g., starting from xylylene dibromide (C6H4(CH2Br)2). Structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extended Porphyrins
Porphyrins ( ) are heterocyclic, macrocyclic, organic compounds, composed of four modified pyrrole subunits interconnected at their α carbon atoms via methine bridges (). In vertebrates, an essential member of the porphyrin group is heme, which is a component of hemoproteins, whose functions include carrying oxygen in the bloodstream. In plants, an essential porphyrin derivative is chlorophyll, which is involved in light harvesting and electron transfer in photosynthesis. The parent of porphyrins is porphine, a rare chemical compound of exclusively theoretical interest. Substituted porphines are called porphyrins. With a total of 26 π-electrons the porphyrin ring structure is a coordinated aromatic system. One result of the large conjugated system is that porphyrins absorb strongly in the visible region of the electromagnetic spectrum, i.e. they are deeply colored. The name "porphyrin" derives . Structure Porphyrin complexes consist of a square planar MN4 core. The periph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liebigs Annalen Der Chemie
''Justus Liebig's Annalen der Chemie'' (often cited as ''Liebigs Annalen'') was one of the oldest and historically most important journals in the field of organic chemistry worldwide. It was established in 1832 and edited by Justus von Liebig with Friedrich Wöhler and others until Liebig's death in 1873. The journal was originally titled ''Annalen der Pharmacie''; its name was changed to ''Justus Liebig's Annalen der Chemie'' in 1874. In its first decades of publishing, the journal was both a periodical containing news of the chemical and pharmaceutical fields and a publisher of primary research. During this time, it was noted to contain rebuttals and criticism of the works it published, inserted by Justus von Liebig during his tenure as an editor. After 1874, changes were made to editorial policies, and the journal published only completed research; later on, in the 20th century, its focus was narrowed to only print articles on organic chemistry, though it had always placed emph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decarboxylation
Decarboxylation is a chemical reaction that removes a carboxyl group and releases carbon dioxide (CO2). Usually, decarboxylation refers to a reaction of carboxylic acids, removing a carbon atom from a carbon chain. The reverse process, which is the first chemical step in photosynthesis, is called carboxylation, the addition of CO2 to a compound. Enzymes that catalyze decarboxylations are called decarboxylases or, the more formal term, carboxy-lyases (Enzyme Commission number, EC number 4.1.1). In organic chemistry The term "decarboxylation" usually means replacement of a carboxyl group () with a hydrogen atom: : Decarboxylation is one of the oldest known organic reactions. It is one of the processes assumed to accompany pyrolysis and destructive distillation. Overall, decarboxylation depends upon stability of the carbanion synthon , although the anion may not be a true chemical intermediate. Typically, carboxylic acids decarboxylate slowly, but carboxylic acids with an α el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Journal Of Organic Chemistry
The ''European Journal of Organic Chemistry'' is a weekly peer-reviewed scientific journal covering organic chemistry. It is published by Wiley-VCH on behalf of Chemistry Europe. The journal, along with the ''European Journal of Inorganic Chemistry'', was established in 1998 as the result of a merger of '' Chemische Berichte/Recueil,'' ''Bulletin de la Société Chimique de France,'' ''Bulletin des Sociétés Chimiques Belges,'' ''Gazzetta Chimica Italiana,'' ''Recueil des Travaux Chimiques des Pays-Bas'', ''Anales de Química,'' ''Chimika Chronika,'' ''Revista Portuguesa de Química, and'' ''ACH-Models in Chemistry.'' According to the ''Journal Citation Reports'', the journal has a 2021 impact factor of 3.261. See also *List of chemistry journals *''European Journal of Inorganic Chemistry The ''European Journal of Inorganic Chemistry'' is a weekly peer-reviewed scientific journal covering inorganic chemistry, inorganic, Organometallic chemistry, organometallic, Bioinorganic chem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahedron (journal)
''Tetrahedron'' is a weekly peer-reviewed scientific journal covering the field of organic chemistry. According to the ''Journal Citation Reports'', ''Tetrahedron'' has a 2020 impact factor of 2.1. ''Tetrahedron'' and Elsevier, its publisher, support an annual symposium. In 2010, complaints were raised over its high subscription cost. Notable papers , the Web of Science lists ten papers from ''Tetrahedron'' that have more than 1000 citations. The four articles that have been cited more than 2000 times are: * – cited 2228 times * – cited 2162 times * – cited 2124 times * – cited 2107 times See also * ''Tetrahedron Letters'' * '' Tetrahedron Computer Methodology'' * ''Polyhedron In geometry, a polyhedron (: polyhedra or polyhedrons; ) is a three-dimensional figure with flat polygonal Face (geometry), faces, straight Edge (geometry), edges and sharp corners or Vertex (geometry), vertices. The term "polyhedron" may refer ...'' (journal) Reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
