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Spiro Compounds
In organic chemistry, spiro compounds are compounds that have at least two molecular rings sharing one common atom. Simple spiro compounds are bicyclic (having just two rings). The presence of only one common atom connecting the two rings distinguishes spiro compounds from other bicyclics.For all four categories, see The specific chapters can be found aan respectively, same access date. For the description featuring adjacent atoms for all but the isolated category, see Clayden, op. cit. Spiro compounds may be fully carbocyclic (all carbon) or heterocyclic (having one or more non-carbon atom). One common type of spiro compound encountered in educational settings is a heterocyclic one— the acetal formed by reaction of a diol with a cyclic ketone. The common atom that connects the two (or sometimes three) rings is called the ''spiro atom''. In carbocyclic spiro compounds like spiro .5ndecane, the spiro-atom is a quaternary carbon, and as the ''-ane'' ending implies, these ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CSD CIF VOPHAJ
CSD may refer to: Finance * Central securities depository * Confederate States Dollar * Serbian dinar, by previous ISO 4217 code Organizations Education * California School for the Deaf (other), several institutions * Canyons School District, in Utah, US * Cheltenham School District, in Pennsylvania, US * Christina School District, in Delaware, US * Cleveland School District, in Mississippi, US * Cordova School District, in Alaska, US Other organizations * Canteen Stores Department (India), a chain of stores operated by the Indian Ministry of Defence at military bases * CSD Pakistan (Canteen Stores Department), a chain of stores operated by the Pakistani Ministry of Defence * Chartered Society of Designers, a British learned society for various kinds of design work * Commission on Sustainable Development (1992–2013), a former UN agency * Communication Service for the Deaf, an American non-profit company providing ASL services * Congress of Democratic Trade Unions (Que ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chiral Compound
In chemistry, a molecule or ion is called chiral () if it cannot be superposed on its mirror image by any combination of rotations, translations, and some conformational changes. This geometric property is called chirality (). The terms are derived from Ancient Greek (''cheir'') 'hand'; which is the canonical example of an object with this property. A chiral molecule or ion exists in two stereoisomers that are mirror images of each other, called enantiomers; they are often distinguished as either "right-handed" or "left-handed" by their absolute configuration or some other criterion. The two enantiomers have the same chemical properties, except when reacting with other chiral compounds. They also have the same physical properties, except that they often have opposite optical activities. A homogeneous mixture of the two enantiomers in equal parts is said to be racemic, and it usually differs chemically and physically from the pure enantiomers. Chiral molecules will usually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Society Reviews
''Chemical Society Reviews'' is a biweekly peer-reviewed scientific journal published by the Royal Society of Chemistry, for review articles on topics of current interest in chemistry. Its predecessors were ''Quarterly Reviews, Chemical Society'' (1947–1971) and ''Royal Institute of Chemistry, Reviews'' (1968–1971); it maintained its current title since 1972. According to the ''Journal Citation Reports'', the journal has a 2023 impact factor of 40.4. The current editor-in-chief (chair of editorial board) is Jennifer Love (University of Calgary). ''Chemical Society Reviews'' publishes occasional themed issues on new and emerging areas of research in the chemical sciences. These issues are edited by a guest editor who is a specialist in their field. Since 2005, ''Chemical Society Reviews'' has published reviews on topics of broad appeal, termed "social interest" reviews, such as articles on art conservation, forensics, and automotive fuels. The journal is abstracted and indexed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chirality
Chirality () is a property of asymmetry important in several branches of science. The word ''chirality'' is derived from the Greek (''kheir''), "hand", a familiar chiral object. An object or a system is ''chiral'' if it is distinguishable from its mirror image; that is, it cannot be superposed (not to be confused with superimposed) onto it. Conversely, a mirror image of an ''achiral'' object, such as a sphere, cannot be distinguished from the object. A chiral object and its mirror image are called '' enantiomorphs'' (Greek, "opposite forms") or, when referring to molecules, ''enantiomers''. A non-chiral object is called ''achiral'' (sometimes also ''amphichiral'') and can be superposed on its mirror image. The term was first used by Lord Kelvin in 1893 in the second Robert Boyle Lecture at the Oxford University Junior Scientific Club which was published in 1894: Human hands are perhaps the most recognized example of chirality. The left hand is a non-superposable mirror ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycol
A diol is a chemical compound containing two hydroxyl groups ( groups). An aliphatic diol may also be called a glycol. This pairing of functional groups is pervasive, and many subcategories have been identified. They are used as protecting groups of carbonyl groups, making them essential in synthesis of organic chemistry. The most common industrial diol is ethylene glycol. Examples of diols in which the hydroxyl functional groups are more widely separated include 1,4-butanediol and propylene-1,3-diol, or beta propylene glycol, . Synthesis of classes of diols Geminal diols A geminal diol has two hydroxyl groups bonded to the same atom. These species arise by hydration of the carbonyl compounds. The hydration is usually unfavorable, but a notable exception is formaldehyde which, in water, exists in equilibrium with methanediol H2C(OH)2. Another example is (F3C)2C(OH)2, the hydrated form of hexafluoroacetone. Many gem-diols undergo further condensation to give dimer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclohexanone
Cyclohexanone is the organic compound with the formula (CH2)5CO. The molecule consists of six-carbon cyclic molecule with a ketone functional group. This colorless oily liquid has a sweet odor reminiscent of benzaldehyde. Over time, samples of cyclohexanone assume a pale yellow color. Cyclohexanone is slightly soluble in water and miscible with common organic solvents. Millions of tonnes are produced annually, mainly as a precursor to nylon. History and synthesis The compound was discovered by in 1888 among the products of AC electrolysis of slightly acidified water solutions of phenol. He named it hydrophenoketone and correctly suggested that phenol was first hydrogenated by electrolytic hydrogen to cyclohexanol, which he wasn't able to isolate, and then oxidized by electrolytic oxygen. Laboratory synthesis Cyclohexanone can be prepared from cyclohexanol by oxidation with chromium trioxide ( Jones oxidation). An alternative method utilizes the safer and more readily avai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dithiol
In organic chemistry, a dithiol is a type of organosulfur compound with two thiol () functional groups. Their properties are generally similar to those of monothiols in terms of solubility, odor, and volatility. They can be classified according to the relative location of the two thiol groups on the organic backbone. File:C6H4(SH)2.svg, Benzene-1,2-dithiol, the parent aromatic dithiol File:1,3-Propandithiol Structural Formula V1.svg, Propane-1,3-dithiol File:Meso-2,3-dimercaptosuccinic-acid-2D-skeletal-A-configurations-labelled.png, The drug meso-2,3- dimercaptosuccinic acid File:Dimercaprol.svg, Dimercaprol ("British anti-Lewisite"), an early antidote for arsenic poisoning File:Dihydrolipoic-acid-2D-skeletal.png, Dihydrolipoic acid, a vitamin File:Dithiothreitol.png, Dithiothreitol, a reagent in protein biochemistry Geminal dithiols Geminal dithiols have the formula RR'C(SH)2. They are formally derived from aldehydes and ketones by the action of hydrogen sulfide. Their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium
Ammonium is a modified form of ammonia that has an extra hydrogen atom. It is a positively charged (cationic) polyatomic ion, molecular ion with the chemical formula or . It is formed by the protonation, addition of a proton (a hydrogen nucleus) to ammonia (). Ammonium is also a general name for positively charged (protonated) substituted amines and quaternary ammonium cations (), where one or more hydrogen atoms are replaced by Organic compound, organic or other groups (indicated by R). Not only is ammonium a source of nitrogen and a key metabolite for many living organisms, but it is an integral part of the global nitrogen cycle. As such, human impact in recent years could have an effect on the biological communities that depend on it. Acid–base properties The ammonium ion is generated when ammonia, a weak base, reacts with Brønsted–Lowry acid–base theory, Brønsted acids (proton donors): : The ammonium ion is mildly acidic, reacting with Brønsted bases to return ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen
Nitrogen is a chemical element; it has Symbol (chemistry), symbol N and atomic number 7. Nitrogen is a Nonmetal (chemistry), nonmetal and the lightest member of pnictogen, group 15 of the periodic table, often called the Pnictogen, pnictogens. It is a common element in the universe, estimated at Abundance of the chemical elements, seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element chemical bond, bond to form N2, a colourless and odourless diatomic molecule, diatomic gas. N2 forms about 78% of Atmosphere of Earth, Earth's atmosphere, making it the most abundant chemical species in air. Because of the volatility of nitrogen compounds, nitrogen is relatively rare in the solid parts of the Earth. It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772 and independently by Carl Wilhelm Scheele and Henry Cavendish at about the same time. The name was suggested by French chemist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketal Synthesis V
In organic chemistry, an acetal is a functional group with the connectivity . Here, the R groups can be organic fragments (a carbon atom, with arbitrary other atoms attached to that) or hydrogen, while the R' groups must be organic fragments not hydrogen. The two R' groups can be equivalent to each other (a "symmetric acetal") or not (a "mixed acetal"). Acetals are formed from and convertible to aldehydes or ketones and have the same oxidation state at the central carbon, but have substantially different chemical stability and reactivity as compared to the analogous carbonyl compounds. The central carbon atom has four bonds to it, and is therefore saturated and has tetrahedral geometry. The term ketal is sometimes used to identify structures associated with ketones (both R groups organic fragments rather than hydrogen) rather than aldehydes and, historically, the term acetal was used specifically for the aldehyde-related cases (having at least one hydrogen in place of an R on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
