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Thiocyanuric Acid
Thiocyanuric acid is the organosulfur compound with the formula . It is analogous to cyanuric acid (). Cyanuric acid is white whereas thiocyanuric acid is yellow. It can also be viewed as a trimeric thioamide. Structure It is a planar molecular as determined by X-ray crystallography. Like cyanuric acid, thiocyanuric acid forms extended hydrogen-bonded network resulting in a sheet-like structure. This arrangement is relevant to the high melting point of the compound. Synthesis, reactions, applications Thiocyanuric acid precipitates from warm, acidic solutions of thiocyanic acid. A modern synthesis begins instead with a preformed ring: cyanuric chloride reacts with sodium hydrosulfide to give table salt and thiocyanuric acid. The compound is mildly acidic, with pKa In chemistry, an acid dissociation constant (also known as acidity constant, or acid-ionization constant; denoted ) is a quantitative measure of the strength of an acid in solution. It is the equilibriu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organosulfur Compound
Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature is abound with organosulfur compounds—sulfur is vital for life. Of the 20 common amino acids, two ( cysteine and methionine) are organosulfur compounds, and the antibiotics penicillin and sulfa drugs both contain sulfur. While sulfur-containing antibiotics save many lives, sulfur mustard is a deadly chemical warfare agent. Fossil fuels, coal, petroleum, and natural gas, which are derived from ancient organisms, necessarily contain organosulfur compounds, the removal of which is a major focus of oil refineries. Sulfur shares the chalcogen group with oxygen, selenium, and tellurium, and it is expected that organosulfur compounds have similarities with carbon–oxygen, carbon–selenium, and car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanuric Acid
Cyanuric acid or 1,3,5-triazine-2,4,6-triol is a chemical compound with the chemical formula, formula (CNOH)3. Like many industrially useful chemicals, this triazine has many synonyms. This white, odorless solid finds use as a precursor or a component of bleaches, disinfectants, and herbicides. In 1997, worldwide production was 160 000 tonnes.Klaus Huthmacher, Dieter Most "Cyanuric Acid and Cyanuric Chloride" Ullmann's Encyclopedia of Industrial Chemistry" 2005, Wiley-VCH, Weinheim. doi 10.1002/14356007.a08 191 Properties and synthesis Properties Cyanuric acid can be viewed as the cyclic trimer (chemistry), trimer of the elusive chemical species Isocyanic acid#cyanicacid2025-03-05, cyanic acid, HOCN. The ring can readily interconvert between several chemical structure, structures via Lactam#Lactam–lactim tautomerism, lactam–lactim tautomerism. Although the triol tautomer may have aromatic character, the keto form predominates in solution. The hydroxyl (-OH) groups ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thioamide
A thioamide (rarely, thionamide, but also known as thiourylenes) is a functional group with the general structure , where are any groups (typically organyl groups or hydrogen). Analogous to amides, thioamides exhibit greater multiple bond character along the C-N bond, resulting in a larger rotational barrier. Synthesis Thioamides are typically prepared by treating amides with phosphorus sulfides such as phosphorus pentasulfide, a reaction first described in the 1870s. An alternative to P2S5 is its more soluble analogue Lawesson's reagent. The Willgerodt-Kindler reaction can give benzylthioamides via an analogous process. These transformations can be seen in the synthesis of tolrestat. : The reaction of nitriles with hydrogen sulfide also affords thioamides: : Imidoyl chlorides react with hydrogen sulfide to produce thioamides. : Reactions A well-known thioamide is thioacetamide, which is used as a source of the sulfide ion. Thioamides are precursors to heterocycles. Such ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring the angles and intensities of the X-ray diffraction, a crystallography, crystallographer can produce a three-dimensional picture of the density of electrons within the crystal and the positions of the atoms, as well as their chemical bonds, crystallographic disorder, and other information. X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences between various materials, especially minerals and alloys. The method has also revealed the structure and function of many biological molecules, including vitamins, drugs, proteins and nucleic acids such as DNA. X-ray crystall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen-bond
In chemistry, a hydrogen bond (H-bond) is a specific type of molecular interaction that exhibits partial covalent character and cannot be described as a purely electrostatic force. It occurs when a hydrogen (H) atom, covalently bonded to a more electronegative donor atom or group (Dn), interacts with another electronegative atom bearing a lone pair of electrons—the hydrogen bond acceptor (Ac). Unlike simple dipole–dipole interactions, hydrogen bonding arises from charge transfer (nB → σ*AH), orbital interactions, and quantum mechanical delocalization, making it a resonance-assisted interaction rather than a mere electrostatic attraction. The general notation for hydrogen bonding is Dn−H···Ac, where the solid line represents a polar covalent bond, and the dotted or dashed line indicates the hydrogen bond. The most frequent donor and acceptor atoms are nitrogen (N), oxygen (O), and fluorine (F), due to their high electronegativity and ability to engage in stronger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiocyanic Acid
Thiocyanic acid is a chemical compound with the formula and structure , which exists as a tautomer with isothiocyanic acid (). The isothiocyanic acid tautomer tends to dominate with the compound being about 95% isothiocyanic acid in the vapor phase. : It is a moderately strong acid, with a p''K''a of 1.1 at 20 °C and extrapolated to zero ionic strength. One of the thiocyanic acid tautomers, HSCN, is predicted to have a triple bond between carbon and nitrogen. Thiocyanic acid has been observed spectroscopically. The salts and esters of thiocyanic acid are known as thiocyanates. The salts are composed of the thiocyanate ion () and a suitable cation (e.g., potassium thiocyanate Potassium thiocyanate is the chemical compound with the molecular formula KSCN. It is an important salt of the thiocyanate anion, one of the pseudohalides. The compound has a low melting point relative to most other inorganic salts. Uses Ch ..., KSCN). The esters of thiocyanic acid h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanuric Chloride
Cyanuric chloride is an organic compound with the formula (NCCl)3. This white solid is the chlorinated derivative of 1,3,5-triazine. It is the trimer of cyanogen chloride. Cyanuric chloride is the main precursor to the popular but controversial herbicide atrazine. Production Cyanuric chloride is prepared in two steps from hydrogen cyanide via the intermediacy of cyanogen chloride, which is trimerized at elevated temperatures over a carbon catalyst: :HCN + Cl2 → ClCN + HCl : In 2005, approximately 200,000 tons were produced.Klaus Huthmacher, Dieter Most "Cyanuric Acid and Cyanuric Chloride" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. . Industrial uses It is estimated that 70% of cyanuric chloride is used in the preparation of the triazine-class pesticides, especially atrazine. Such reactions rely on the easy displacement of the chloride with nucleophiles such as amines: :(ClCN)3 + 2 RNH2 → (RNHCN)(ClCN)2 + RNH3+Cl− Other tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hydrosulfide
Sodium hydrosulfide is the chemical compound with the formula NaSH. This compound is the product of the half-neutralization of hydrogen sulfide () with sodium hydroxide (NaOH). NaSH and sodium sulfide are used industrially, often for similar purposes. Solid NaSH is colorless. The solid has an odor of owing to hydrolysis by atmospheric moisture. In contrast with sodium sulfide (), which is insoluble in organic solvents, NaSH, being a 1:1 electrolyte, is more soluble. Structure and properties Crystalline NaSH undergoes two phase transitions. At temperatures above 360 K, NaSH adopts the NaCl structure, which implies that the behaves as a spherical anion owing to its rapid rotation, leading to equal occupancy of eight equivalent positions. Below 360 K, a rhombohedral structure forms, and the sweeps out a discoidal shape. Below 114 K, the structure becomes monoclinic. The analogous rubidium and potassium compounds behave similarly. NaSH has a relatively low melting p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Table Salt
In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as rock salt or halite. Salt is essential for life in general (being the source of the essential dietary minerals sodium and chlorine), and saltiness is one of the basic human tastes. Salt is one of the oldest and most ubiquitous food seasonings, and is known to uniformly improve the taste perception of food. Salting, brining, and pickling are ancient and important methods of food preservation. Some of the earliest evidence of salt processing dates to around 6000 BC, when people living in the area of present-day Romania boiled spring water to extract salts; a salt works in China dates to approximately the same period. Salt was prized by the ancient Hebrews, Greeks, Romans, Byzantines, Hittites, Egyptians, and Indians. Salt became an impo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
