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Quinuclidone
Quinuclidones are a class of bicyclic organic compounds with chemical formula C7H11NO with two structural isomers for the base skeleton 3-quinuclidone and 2-quinuclidone. 3-Quinuclidone (1-azabicyclo .2.2ctan-3-one) is an uneventful molecule that can be synthesized as the hydrochloric acid salt in a Dieckman condensation: Organic reduction of this compound gives the compound quinuclidine, structurally related to DABCO, which has one additional bridgehead nitrogen atom. The other isomer, 2-quinuclidone, appears equally uneventful, but in fact it has defied synthesis until 2006. The reason is that this molecule is very unstable because its amide group has the amine lone pair and the carbonyl group not properly aligned, as may be expected for an amide, as a result of steric strain. This behaviour is predicted by Bredt's Rule, and formal amide group resembles in fact an amine, as evidenced by the ease of salt formation. The organic synthesis of the tetrafluoroborate salt of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinuclidone Structures
Quinuclidones are a class of bicyclic organic compounds with chemical formula C7H11NO with two structural isomers for the base skeleton 3-quinuclidone and 2-quinuclidone. 3-Quinuclidone (1-azabicyclo .2.2ctan-3-one) is an uneventful molecule that can be synthesized as the hydrochloric acid salt in a Dieckman condensation: Organic reduction of this compound gives the compound quinuclidine, structurally related to DABCO, which has one additional bridgehead nitrogen atom. The other isomer, 2-quinuclidone, appears equally uneventful, but in fact it has defied synthesis until 2006. The reason is that this molecule is very unstable because its amide group has the amine lone pair and the carbonyl group not properly aligned, as may be expected for an amide, as a result of steric strain. This behaviour is predicted by Bredt's Rule, and formal amide group resembles in fact an amine, as evidenced by the ease of salt formation. The organic synthesis of the tetrafluoroborate salt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicyclic
In chemistry, a bicyclic molecule () is a molecule that features two joined rings. Bicyclic structures occur widely, for example in many biologically important molecules like α-thujene and camphor. A bicyclic compound can be carbocyclic (all of the ring atoms are carbons), or heterocyclic (the rings' atoms consist of at least two elements), like DABCO. Moreover, the two rings can both be aliphatic (''e.g.'' decalin and norbornane), or can be aromatic (''e.g.'' naphthalene), or a combination of aliphatic and aromatic (''e.g.'' tetralin). Three modes of ring junction are possible for a bicyclic compound: * In spirocyclic compounds, the two rings share only one single atom, the spiro atom, which is usually a quaternary carbon. An example of a spirocyclic compound is the photochromic switch spiropyran. * In fused/condensed bicyclic compounds, two rings share two adjacent atoms. In other words, the rings share one covalent bond, ''i.e.'' the so-called bridgehead atoms are directly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonyl
In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups. A compound containing a carbonyl group is often referred to as a carbonyl compound. The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex (a metal carbonyl, e.g. nickel carbonyl). The remainder of this article concerns itself with the organic chemistry definition of carbonyl, where carbon and oxygen share a double bond. Carbonyl compounds In organic chemistry, a carbonyl group characterizes the following types of compounds: Other organic carbonyls are urea and the carbamates, the derivatives of acyl chlorides chloroformates and phosgene, carbonate esters, thioesters, lactones, lactams, hydroxamates, and isocyanates. Examples of inorganic carbonyl compounds are carbon dioxide and carbonyl sulfide. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithium Aluminium Hydride
Lithium aluminium hydride, commonly abbreviated to LAH, is an inorganic compound with the chemical formula Li Al H4. It is a white solid, discovered by Finholt, Bond and Schlesinger in 1947. This compound is used as a reducing agent in organic synthesis, especially for the reduction of esters, carboxylic acids, and amides. The solid is dangerously reactive toward water, releasing gaseous hydrogen (H2). Some related derivatives have been discussed for hydrogen storage. Properties, structure, preparation LAH is a colourless solid but commercial samples are usually gray due to contamination. This material can be purified by recrystallization from diethyl ether. Large-scale purifications employ a Soxhlet extractor. Commonly, the impure gray material is used in synthesis, since the impurities are innocuous and can be easily separated from the organic products. The pure powdered material is pyrophoric, but not its large crystals. Some commercial materials contain mineral oil to in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Reduction
Organic reductions or organic oxidations or organic redox reactions are redox reactions that take place with organic compounds. In organic chemistry oxidations and reductions are different from ordinary redox reactions, because many reactions carry the name but do not actually involve electron transfer.March Jerry; (1985). Advanced Organic Chemistry reactions, mechanisms and structure (3rd ed.). New York: John Wiley & Sons, inc. Instead the relevant criterion for organic oxidation is gain of oxygen and/or loss of hydrogen, respectively.''Organic Redox Systems: Synthesis, Properties, and Applications'', Tohru Nishinaga 2016 Simple functional groups can be arranged in order of increasing oxidation state. The oxidation numbers are only an approximation: When methane is oxidized to carbon dioxide its oxidation number changes from −4 to +4. Classical reductions include alkene reduction to alkanes and classical oxidations include oxidation of alcohols to aldehydes. In oxidations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lactone
Lactones are cyclic carboxylic esters, containing a 1-oxacycloalkan-2-one structure (), or analogues having unsaturation or heteroatoms replacing one or more carbon atoms of the ring. Lactones are formed by intramolecular esterification of the corresponding hydroxycarboxylic acids, which takes place spontaneously when the ring that is formed is five- or six-membered. Lactones with three- or four-membered rings (α-lactones and β-lactones) are very reactive, making their isolation difficult. Special methods are normally required for the laboratory synthesis of small-ring lactones as well as those that contain rings larger than six-membered. Nomenclature Lactones are usually named according to the precursor acid molecule (''aceto'' = 2 carbon atoms, ''propio'' = 3, ''butyro'' = 4, ''valero'' = 5, ''capro'' = 6, etc.), with a ''-lactone'' suffix and a Greek letter prefix that specifies the number of carbon atoms in the heterocycle — that is, the distance between the relevant -OH ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meta-Chloroperoxybenzoic Acid
''meta''-Chloroperoxybenzoic acid (mCPBA or ''m''CPBA) is a peroxycarboxylic acid. A white solid, it is used widely as an oxidant in organic synthesis. mCPBA is often preferred to other peroxy acids because of its relative ease of handling. mCPBA is a strong oxidizing agent that may cause fire upon contact with flammable material. Preparation and purification mCPBA can be prepared by reacting m-Chlorobenzoyl chloride with a basic solution of hydrogen peroxide, followed by acidification. It is sold commercially as a shelf-stable mixture that is less than 72% mCPBA, with the balance made up of ''m''-chlorobenzoic acid (10%) and water. The peroxyacid can be purified by washing the commercial material with a sodium hydroxide and potassium phosphate solution buffered at pH = 7.5. Peroxyacids are generally slightly less acidic than their carboxylic acid counterparts, so one can extract the acid impurity by careful control of pH. The purified material is reasonably stable against de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schmidt Reaction
In organic chemistry, the Schmidt reaction is an organic reaction in which an azide reacts with a carbonyl derivative, usually an aldehyde, ketone, or carboxylic acid, under acidic conditions to give an amine or amide, with expulsion of nitrogen. It is named after Karl Friedrich Schmidt (1887–1971), who first reported it in 1924 by successfully converting benzophenone and hydrazoic acid to benzanilide. The intramolecular reaction was not reported until 1991 but has become important in the synthesis of natural products. The reaction is effective with carboxylic acids to give amines (above), and with ketones to give amides (below). Reaction mechanism The reaction is closely related to the Curtius rearrangement except that in this reaction the acyl azide is produced by reaction of the carboxylic acid with hydrazoic acid via the protonated carboxylic acid, in a process akin to a Fischer esterification. An alternative, involving the formation of an acylium ion, becomes more i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketone
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' is methyl), with the formula . Many ketones are of great importance in biology and in industry. Examples include many sugars (ketoses), many steroids (e.g., testosterone), and the solvent acetone. Nomenclature and etymology The word ''ketone'' is derived from ''Aketon'', an old German word for ''acetone''. According to the rules of IUPAC nomenclature, ketone names are derived by changing the suffix ''-ane'' of the parent alkane to ''-anone''. Typically, the position of the carbonyl group is denoted by a number, but traditional nonsystematic names are still generally used for the most important ketones, for example acetone and benzophenone. These nonsystematic names are considere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azide
In chemistry, azide is a linear, polyatomic anion with the formula and structure . It is the conjugate base of hydrazoic acid . Organic azides are organic compounds with the formula , containing the azide functional group. The dominant application of azides is as a propellant in air bags. Preparation Sodium azide is made industrially by the reaction of nitrous oxide, with sodium amide in liquid ammonia as solvent: : Many inorganic azides can be prepared directly or indirectly from sodium azide. For example, lead azide, used in detonators, may be prepared from the metathesis reaction between lead nitrate and sodium azide. An alternative route is direct reaction of the metal with silver azide dissolved in liquid ammonia. Some azides are produced by treating the carbonate salts with hydrazoic acid. Bonding Azide is isoelectronic with carbon dioxide , cyanate , nitrous oxide , nitronium ion and cyanogen fluoride NCF. Per valence bond theory, azide can be described ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norcamphor
Norcamphor is an organic compound, classified as a bicyclic ketone. It is an analog of camphor, but without the three methyl groups. A colorless solid, it is used as a building block in organic synthesis. Norcamphor is prepared from norbornene via the 2-formate ester, which is oxidized. It is a useful precursor to norborneols. See also * Norbornane Norbornane (also known as bicyclo .2.1eptane) is an organic compound and a saturated hydrocarbon with chemical formula C7H12. It is a crystalline compound with a melting point of 88 °C. The carbon skeleton is derived from cyclohexane ring with a ... References Ketones Cyclopentanes Norbornanes {{ketone-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
