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Stilbene Photocyclization
In organic chemistry, the Mallory reaction is a photochemical-cyclization– elimination reaction of diaryl-ethylene structures to form phenanthrenes and other polycyclic form polycyclic aromatic hydrocarbons and heteroaromatics.Mallory, F. B.; Mallory, C. W. '' Org. React.'' 1984, ''30'', 1. This name reaction is named for Frank Mallory, who discovered it while a graduate student. Under UV irradiation, stilbene and its derivatives undergo intramolecular cyclization to form dihydrophenanthrenes. In the presence of an oxidant, the dihydrophenanthrenes aromatize to give polycyclic aromatics. Typically, the dihydrophenanthrenes themselves are relatively unstable, and revert to ''cis''-stilbenes in the absence of a hydrogen-trapping agent. Suitably substituted stilbenes may undergo irreversible, rearomatizing elimination or ,nshift processes in the absence of an oxidant. Aryl enynes, heteroatomic stilbene derivatives (e.g. amides), and substrates containing a single heteroatom in pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J.; Greeves, N. and Warren, S. (2012) ''Organic Chemistry''. Oxford University Press. pp. 1–15. . Study of structure determines their structural formula. Study of properties includes physical and chemical properties, and evaluation of chemical reactivity to understand their behavior. The study of organic reactions includes the chemical synthesis of natural products, drugs, and polymers, and study of individual organic molecules in the laboratory and via theoretical ( in silico) study. The range of chemicals studied in organic chemistry includes hydrocarbons (compounds containing only carbon and hydrogen) as well as compounds based on carbon, but also containing other elements, especially oxygen, nitrogen, sulfur, phosphorus (included in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Orbital
In chemistry, a molecular orbital is a mathematical function describing the location and wave-like behavior of an electron in a molecule. This function can be used to calculate chemical and physical properties such as the probability of finding an electron in any specific region. The terms ''atomic orbital'' and ''molecular orbital'' were introduced by Robert S. Mulliken in 1932 to mean ''one-electron orbital wave functions''. At an elementary level, they are used to describe the ''region'' of space in which a function has a significant amplitude. In an isolated atom, the orbital electrons' location is determined by functions called atomic orbitals. When multiple atoms combine chemically into a molecule, the electrons' locations are determined by the molecule as a whole, so the atomic orbitals combine to form molecular orbitals. The electrons from the constituent atoms occupy the molecular orbitals. Mathematically, molecular orbitals are an approximate solution to the Schrödin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scheme 7 Rev
A scheme is a systematic plan for the implementation of a certain idea. Scheme or schemer may refer to: Arts and entertainment * ''The Scheme'' (TV series), a BBC Scotland documentary series * The Scheme (band), an English pop band * ''The Scheme'', an action role-playing video game for the PC-8801, made by Quest Corporation * Schemer (comics), Richard Fisk, a Marvel Comics villain turned antihero * Horace Schemer, a fictional character in the TV series ''Shining Time Station'' * Schemee, a fictional child character and Schemer's nephew in the TV Series ''Shining Time Station'' * ''Schemers'' (film), a Scottish film Other uses * Classification scheme, eg a thesaurus, a taxonomy, a data model, or an ontology * Scheme (programming language), a minimalist dialect of Lisp * Scheme (mathematics), a concept in algebraic geometry * Scheme (linguistics), a figure of speech that changes a sentence's structure * Scam, an attempt to swindle or cheat people through deception **Get-rich-quick ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylene
Triphenylene is an organic compound with the formula (C6H4)3. A flat polycyclic aromatic hydrocarbon (PAH), it consists of four fused benzene rings. Triphenylene has delocalized 18-''π''-electron systems based on a planar structure, corresponding to the symmetry group ''D''3h. It is a white or colorless solid. Preparation Triphenylene can be isolated from coal tar. It is also be synthesized in various ways. One method is trimerization of benzyne. Another method involves trapping benzyne with a biphenyl derivative. Properties Triphenylene is more resonance stable than its isomers chrysene, benz 'a''nthracene, benzo 'c''henanthrene, and tetracene. For this reason triphenylene resists hydrogenation. As a disc-shaped, planar molecule, triphenylene has attracted attention as the core of discotic mesogen in liquid crystal Liquid crystal (LC) is a state of matter whose properties are between those of conventional liquids and those of solid crystals. For example, a liquid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
