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Acyl Azide
Acyl azides are carboxylic acid derivatives with the general formula RCON3. These compounds, which are a subclass of organic azides, are generally colorless. Preparation Typically acyl azides are generated under conditions where they rearrange to the isocyanate. Alkyl or aryl acyl chlorides react with sodium azide to give acyl azides. : The second major route to azides is from the acyl hydrazides with nitrous acid. Acyl azides have also been synthesized from various carboxylic acids and sodium azide in presence of triphenylphosphine and trichloroacetonitrile catalysts in excellent yields at mild conditions. Another route starts with aliphatic and aromatic aldehydes reacting with iodine azide which is formed from sodium azide and iodine monochloride in acetonitrile. Uses On Curtius rearrangement, acyl azides yield isocyanate In organic chemistry, isocyanate is the functional group with the formula . Organic compounds that contain an isocyanate group are referred to as is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acyl Azide
Acyl azides are carboxylic acid derivatives with the general formula RCON3. These compounds, which are a subclass of organic azides, are generally colorless. Preparation Typically acyl azides are generated under conditions where they rearrange to the isocyanate. Alkyl or aryl acyl chlorides react with sodium azide to give acyl azides. : The second major route to azides is from the acyl hydrazides with nitrous acid. Acyl azides have also been synthesized from various carboxylic acids and sodium azide in presence of triphenylphosphine and trichloroacetonitrile catalysts in excellent yields at mild conditions. Another route starts with aliphatic and aromatic aldehydes reacting with iodine azide which is formed from sodium azide and iodine monochloride in acetonitrile. Uses On Curtius rearrangement, acyl azides yield isocyanate In organic chemistry, isocyanate is the functional group with the formula . Organic compounds that contain an isocyanate group are referred to as is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldehydes
In organic chemistry, an aldehyde () is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl group. Aldehydes are common and play important roles in the technology and biological spheres. Structure and bonding Aldehydes feature a carbon center that is connected by a double bond to oxygen and a single bond to hydrogen and single bond to a third substituent, which is carbon or, in the case of formaldehyde, hydrogen. The central carbon is often described as being sp2- hybridized. The aldehyde group is somewhat polar. The C=O bond length is about 120-122 picometers. Physical properties and characterization Aldehydes have properties that are diverse and that depend on the remainder of the molecule. Smaller aldehydes are more soluble in water, formaldehyde and acetaldehyde completely so. The volatile aldehydes have pungent odors. Aldehy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curtius Rearrangement Scheme
Curtius may refer to: People * Curtia gens, the clan to which the Curtii family belonged ** Marcus Curtius, a noble of early Rome who rode his horse into the Lacus Curtius, which was then named after him ** Quintus Curtius Rufus, 1st century CE historian ** Curtius Rufus. 1st century CE politician, possibly the same as Quintus Curtius Rufus * Curtius baronets, a title in the Baronetcy of England * Albert Curtz (1600–1671), German astronomer and member of the Society of Jesus * Alexander Curtius, Lithuanian nobleman and scholar * Alfred Schulz-Curtius (1853–1918), aka Alfred Curtis, a German classical music impresario * Dirk Donker Curtius (1792–1864), Dutch politician * Ernst Robert Curtius (1886–1956), German scholar, philologist * Ernst Curtius (1814–1896), German archaeologist, historian * Georg Curtius (1820–1885), German philologist * Jacob Curtius (1554–1594), Imperial Pro-Chancellor for Emperor Rudolph II, astronomer, mathematician and instrument maker * Ja ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chem
Chem may refer to: * Chemistry practical waali mam *Chemistry *Chemical * ''Chem'' (journal), a scientific journal published by Cell Press *Post apocalyptic slang for "drugs", medicinal or otherwise in the Fallout video game series. In Ancient Egyptian usage: * ''Khem'' (also spelt ''Chem''), the Egyptian word for "black" * Min (god), in the past erroneously named ''Khem'' CHEM may refer to : *A metabolic panel: for instance, CHEM-7, which is the basic metabolic panel *CHEM-DT CHEM-DT is the TVA owned-and-operated television station in Trois-Rivières, Quebec, Canada. It broadcasts a high-definition digital signal on VHF channel 8 from a transmitter on Rue Principale in Notre-Dame-du-Mont-Carmel. Owned by the Grou ..., a Canadian television channel See also * Chemo (other) * Kemi, a place in Finland {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isocyanate
In organic chemistry, isocyanate is the functional group with the formula . Organic compounds that contain an isocyanate group are referred to as isocyanates. An organic compound with two isocyanate groups is known as a diisocyanate. Diisocyanates are manufactured for the production of polyurethanes, a class of polymers. Isocyanates should not be confused with cyanate esters and isocyanides, very different families of compounds. The cyanate (cyanate ester) functional group () is arranged differently from the isocyanate group (). Isocyanides have the connectivity , lacking the oxygen of the cyanate groups. Structure and bonding In terms of bonding, isocyanates are closely related to carbon dioxide (CO2) and carbodiimides (C(NR)2). The C−N=C=O unit that defines isocyanates is planar, and the N=C=O linkage is nearly linear. In phenyl isocyanate, the C=N and C=O distances are respectively 1.195 and 1.173 Å. The C-N=C angle is 134.9° and the N=C=O angle is 173.1°. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curtius Rearrangement
The Curtius rearrangement (or Curtius reaction or Curtius degradation), first defined by Theodor Curtius in 1885, is the thermal decomposition of an acyl azide to an isocyanate with loss of nitrogen gas. The isocyanate then undergoes attack by a variety of nucleophiles such as water, alcohols and amines, to yield a primary amine, carbamate or urea derivative respectively. Several reviews have been published. Preparation of acyl azide The acyl azide is usually made from the reaction of acid chlorides or anydrides with sodium azide or trimethylsilyl azide. Acyl azides are also obtained from treating acylhydrazines with nitrous acid. Alternatively, the acyl azide can be formed by the direct reaction of a carboxylic acid with diphenylphosphoryl azide (DPPA). Reaction mechanism It was believed that the Curtius rearrangement was a two-step processes, with the loss of nitrogen gas forming an acyl nitrene, followed by migration of the R-group to give the isocyanate. However, recent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine Monochloride
Iodine monochloride is an interhalogen compound with the formula . It is a red-brown chemical compound that melts near room temperature. Because of the difference in the electronegativity of iodine and chlorine, this molecule is highly polar and behaves as a source of I+. Preparation Iodine monochloride is produced simply by combining the halogens in a 1:1 molar ratio, according to the equation : When chlorine gas is passed through iodine crystals, one observes the brown vapor of iodine monochloride. Dark brown iodine monochloride liquid is collected. Excess chlorine converts iodine monochloride into iodine trichloride in a reversible reaction: : Polymorphs has two polymorphs; α-ICl, which exists as black needles (red by transmitted light) with a melting point of 27.2 °C, and β-ICl, which exists as black platelets (red-brown by transmitted light) with a melting point 13.9 °C.Brisbois, R. G.; Wanke, R. A.; Stubbs, K. A.; Stick, R. V. "Iodine Monochloride" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine Azide
Iodine azide () is an explosive inorganic compound, which in ordinary conditions is a yellow solid. Formally, it is an inter-pseudohalogen. Preparation Iodine azide can be prepared from the reaction between silver azide and elemental iodine: : Since silver azide can only be handled safely while moist, but even small traces of water cause the iodine azide to decompose, this synthesis is done by suspending the silver azide in dichloromethane and adding a drying agent before reaction with the iodine. In this way, a pure solution of iodine azide results, which can then be carefully evaporated to form needle-shaped golden crystals. This reaction was used in the original synthesis of iodine azide in 1900, where it was obtained as unstable solutions in ether and impure crystals contaminated by iodine. Iodine azide can also be generated ''in situ'' by reacting iodine monochloride and sodium azide under conditions where it is not explosive. Properties In the solid state, io ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synlett
''Synlett'' is an international scientific journal for accounts and rapid communications of original contributions of fundamental research in synthetic organic chemistry. The impact factor of this journal is 2.419 (2017). ''Nature'' featured a brief piece by the editor-in-chief of the journal in 2017, Benjamin List Benjamin ( he, ''Bīnyāmīn''; "Son of (the) right") blue letter bible: https://www.blueletterbible.org/lexicon/h3225/kjv/wlc/0-1/ H3225 - yāmîn - Strong's Hebrew Lexicon (kjv) was the last of the two sons of Jacob and Rachel (Jacob's thir ..., where he discussed the journal's experience with the non-traditional peer review system. References Chemistry journals Thieme academic journals Publications established in 1989 {{chem-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxylic Acid
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
