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Hydroxylamine-O-sulfonic Acid
Hydroxylamine-''O''-sulfonic acid (HOSA) is the inorganic compound with molecular formula H3NO4S that is formed by the sulfonation of hydroxylamine with oleum. It is a white, water-soluble and hygroscopic, solid, commonly represented by the condensed structural formula H2NOSO3H, though it actually exists as a zwitterion and thus is more accurately represented as +H3NOSO3−. It is used as a reagent for the introduction of amine groups (–NH2), for the conversion of aldehydes into nitriles and alicyclic compound, alicyclic ketones into lactams (cyclic amides), and for the synthesis of variety of nitrogen-containing heterocycles. Preparation According to a laboratory procedure hydroxylamine-''O''-sulfonic acid can be prepared by treating hydroxylamine sulfate with fuming sulfuric acid (oleum). The industrial process is similar. :(NH3OH)2SO4 + 2SO3 → 2H2NOSO3H + H2SO4 The sulfonation of hydroxylamine can also be effected with chlorosulfonic acid by a method first pub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Compound
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep mantle remain active areas of investigation. Some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, etc.), carbon monoxide, carbon dioxide, carbides, and the following salts of inorganic anions: carbonates, cyanides, cyanates, and thiocyanates. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it does not occur within living things. History Friedrich Wöhler's conversion of ammonium cyanate into urea in 1828 is often cited as the starting point of modern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encyclopedia Of Reagents For Organic Synthesis
The ''Encyclopedia of Reagents for Organic Synthesis'' is published in print and online by John Wiley & Sons Ltd. The online version is also known as e-EROS. The encyclopedia contains a description of the use of reagents used in organic chemistry. The eight-volume print version includes 3500 alphabetically arranged articles and the online version is regularly updated to include new reagents and catalyst Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...s. References External links *Print version Encyclopedias of science Chemistry books {{encyclopedia-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrophile
In chemistry, an electrophile is a chemical species that forms bonds with nucleophiles by accepting an electron pair. Because electrophiles accept electrons, they are Lewis acids. Most electrophiles are positively charged, have an atom that carries a partial positive charge, or have an atom that does not have an octet of electrons. Electrophiles mainly interact with nucleophiles through addition and substitution reactions. Frequently seen electrophiles in organic syntheses include cations such as H+ and NO+, polarized neutral molecules such as HCl, alkyl halides, acyl halides, and carbonyl compounds, polarizable neutral molecules such as Cl2 and Br2, oxidizing agents such as organic peracids, chemical species that do not satisfy the octet rule such as carbenes and radicals, and some Lewis acids such as BH3 and DIBAL. Organic chemistry Addition of halogens These occur between alkenes and electrophiles, often halogens as in halogen addition reactions. Common reactions i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleophile
In chemistry, a nucleophile is a chemical species that forms bonds by donating an electron pair. All molecules and ions with a free pair of electrons or at least one pi bond can act as nucleophiles. Because nucleophiles donate electrons, they are Lewis bases. ''Nucleophilic'' describes the affinity of a nucleophile to bond with positively charged atomic nuclei. Nucleophilicity, sometimes referred to as nucleophile strength, refers to a substance's nucleophilic character and is often used to compare the affinity of atoms. Neutral nucleophilic reactions with solvents such as alcohols and water are named solvolysis. Nucleophiles may take part in nucleophilic substitution, whereby a nucleophile becomes attracted to a full or partial positive charge, and nucleophilic addition. Nucleophilicity is closely related to basicity. History The terms ''nucleophile'' and ''electrophile'' were introduced by Christopher Kelk Ingold in 1933, replacing the terms ''anionoid'' and ''cationoid' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordinate Covalent Bond
In coordination chemistry, a coordinate covalent bond, also known as a dative bond, dipolar bond, or coordinate bond is a kind of two-center, two-electron covalent bond in which the two electrons derive from the same atom. The bonding of metal ions to ligands involves this kind of interaction. This type of interaction is central to Lewis acid–base theory. Coordinate bonds are commonly found in coordination compounds. Examples Coordinate covalent bonding is ubiquitous. In all metal aquo-complexes (H2O)''n'''m''+, the bonding between water and the metal cation is described as a coordinate covalent bond. Metal-ligand interactions in most organometallic compounds and most coordination compounds are described similarly. The term ''dipolar bond'' is used in organic chemistry for compounds such as amine oxides for which the electronic structure can be described in terms of the basic amine donating two electrons to an oxygen atom. : → O The arrow → indicates that both ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfamic Acid
Sulfamic acid, also known as amidosulfonic acid, amidosulfuric acid, aminosulfonic acid, sulphamic acid and sulfamidic acid, is a molecular compound with the formula H3NSO3. This colourless, water-soluble compound finds many applications. Sulfamic acid melts at 205 °C before decomposing at higher temperatures to water, sulfur trioxide, sulfur dioxide and nitrogen. Sulfamic acid (H3NSO3) may be considered an intermediate compound between sulfuric acid (H2SO4), and sulfamide (H4N2SO2), effectively replacing a hydroxyl (–OH) group with an amine (–NH2) group at each step. This pattern can extend no further in either direction without breaking down the sulfonyl (–SO2–) moiety. Sulfamates are derivatives of sulfamic acid. Production Sulfamic acid is produced industrially by treating urea with a mixture of sulfur trioxide and sulfuric acid (or oleum). The conversion is conducted in two stages, the first being sulfamation: :OC(NH2)2 + SO3 → OC(NH2)(NHSO3H) :OC(NH2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Syntheses
''Organic Syntheses'' is a peer-reviewed scientific journal that was established in 1921. It publishes detailed and checked procedures for the synthesis of organic compounds. A unique feature of the review process is that all of the data and experiments reported in an article must be successfully repeated in the laboratory of a member of the editorial board as a check for reproducibility prior to publication. The journal is published by Organic Syntheses, Inc., a non-profit corporation. An annual print version is published by John Wiley & Sons on behalf of Organic Syntheses, Inc. History Prior to World War I, work on synthetic organic chemistry in the United States had been quite limited, and most of the reagents used in laboratories had to be imported from Europe. When export stoppages and trade embargoes cut off this source, Clarence Derick, a professor of chemistry at University of Illinois at Urbana-Champaign, began an effort to synthesize these needed chemicals in industr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorosulfonic Acid
Chlorosulfuric acid (IUPAC name: sulfurochloridic acid) is the inorganic compound with the formula HSO3Cl. It is also known as chlorosulfonic acid, being the sulfonic acid of chlorine. It is a distillable, colorless liquid which is hygroscopic and a powerful lachrymator. Commercial samples usually are pale brown or straw colored. Salts and esters of chlorosulfuric acid are known as chlorosulfates. Structure and properties Chlorosulfuric acid is a tetrahedral molecule. The formula is more descriptively written SO2(OH)Cl, but HSO3Cl is traditional. It is an intermediate, chemically and conceptually, between sulfuryl chloride (SO2Cl2) and sulfuric acid (H2SO4). The compound is rarely obtained pure. Upon standing with excess sulfur trioxide, it decomposes to pyrosulfuryl chlorides: :2 ClSO3H + SO3 → H2SO4 + S2O5Cl2 Synthesis The industrial synthesis entails the reaction of hydrogen chloride with a solution of sulfur trioxide in sulfuric acid: :HCl + SO3 → ClSO3H It can als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
