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Thiourea Dioxide
Thiourea dioxide or thiox is an organosulfur compound that is used in the textile industry. It functions as a reducing agent. It is a white solid, and exhibits tautomerism in solution. Structure Crystalline and gaseous thiourea dioxide adopts a C2v-symmetric structure. Selected bond lengths: S-C = 186, C-N = 130, and S-O = 149 pm. The sulfur center is pyramidal. The C-S bond length is close to that of a single bond. For comparison, the C=S bond in thiourea is 171 pm. Instead the bonding is described with a significant contribution from a dipolar resonance structure with multiple bonding between C and N. One consequence of this bonding is the planarity of the nitrogen centers. In the presence of water or DMSO, thiourea dioxide converts to the tautomer, a sulfinic acid, (H2N)HN=CS(O)(OH), named formamidine sulfinic acid. Synthesis Thiourea dioxide was first prepared in 1910 by the English chemist Edward de Barry Barnett. Thiourea dioxide is prepared by the oxidation of thiourea ... [...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] |
Urea
Urea, also called carbamide (because it is a diamide of carbonic acid), is an organic compound with chemical formula . This amide has two Amine, amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid. Urea serves an important role in the cellular metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals. ''Urea'' is Neo-Latin, , , itself from Proto-Indo-European ''*h₂worsom''. It is a colorless, odorless solid, highly soluble in water, and practically non-toxic ( is 15 g/kg for rats). Dissolved in water, it is neither acidic nor base (chemistry), alkaline. The body uses it in many processes, most notably metabolic waste#Nitrogen wastes, nitrogen excretion. The liver forms it by combining two ammonia molecules () with a carbon dioxide () molecule in the urea cycle. Urea is widely used in fertilizers as a source of nitrogen (N) and is an important ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amidines
Amidines are organic compounds with the functional group RC(NR)NR2, where the R groups can be the same or different. They are the imine derivatives of amides (RC(O)NR2). The simplest amidine is formamidine, HC(=NH)NH2. Examples of amidines include: * DBU * diminazene * benzamidine * Pentamidine * Paranyline Preparation A common route to primary amidines is the Pinner reaction. Reaction of the nitrile with alcohol in the presence of acid gives an iminoether. Treatment of the resulting compound with ammonia then completes the conversion to the amidine. Instead of using a Bronsted acid, Lewis acids such as aluminium trichloride promote the direct amination of nitriles, or, in certain exceptional cases, of amides. Dimethylformamide acetal reacts with primary amines to give amidines: :Me2NC(H)(OMe)2 + RNH2 → Me2NC=NHR + 2 MeOH Catalysis is likewise not required for direct amination of an imidoyl chloride. Amidines are also prepared by the addition of organolithi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thioureas
In organic chemistry, thioureas are members of a family of organosulfur compounds with the formula and structure . The parent member of this class of compounds is thiourea (). Substituted thioureas are found in several commercial chemicals. Structure and bonding Thioureas have a trigonal planar molecular geometry of the core. The bond distance is near 1.71 Å, which is 0.1 Å longer than in normal ketones (). The C–N bond distances are short. Thioureas occurs in two tautomeric forms. : On the other hand, some compounds depicted as isothioureas and in fact thioureas, one example being mercaptobenzimidazole. Synthesis ''N'',''N''′-unsubstituted thioureas can be prepared by treating the corresponding cyanamide with hydrogen sulfide or similar sulfide sources. Organic ammonium salts react with potassium thiocyanate as the source of the thiocarbonyl (). Alternatively, ''N'',''N''′-disubstituted thioureas can be prepared by coupling two amines with thiophosgen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfinic Acids
Sulfinic acids are oxoacids of sulfur with the structure RSO(OH). In these organosulfur compounds, sulfur is pyramidal. Structure and properties Sulfinic acids RSO2H are typically more acidic than the corresponding carboxylic acid RCO2H. Sulfur is pyramidal, consequently sulfinic acids are chiral. The free acids are typically unstable, disproportionating to the sulfonic acid RSO3H and thiosulfonate RSSO2R. The formal anhydride of a sulfinic acid has no oxygen atom bridge, but is instead a sulfinyl sulfone (R–S+(–O−)–S2+(–O−)2–), and disproportionation is believed to occur through the free-radical fission of this intermediate. Alkylation of sulfinic acids can give either sulfones or sulfinate esters, depending on the solvent and reagent. Strongly polarized reactants (e.g. trimethyloxonium tetrafluoroborate) give esters, whereas relatively unpolarized reactants (e.g. an alkyl halide or enone) give sulfones. Sulfinates react with G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketones
In organic chemistry, a ketone is an organic compound with the structure , where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group (a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' are methyl), with the formula . Many ketones are of great importance in biology and 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 considered retained IUPAC names, although some introd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatic
In organic chemistry, aromaticity is a chemical property describing the way in which a conjugated system, conjugated ring of unsaturated bonds, lone pairs, or empty orbitals exhibits a stabilization stronger than would be expected from conjugation alone. The earliest use of the term was in an article by August Wilhelm Hofmann in 1855. There is no general relationship between aromaticity as a chemical property and the olfaction, olfactory properties of such compounds. Aromaticity can also be considered a manifestation of cyclic delocalization and of Resonance (chemistry), resonance. This is usually considered to be because electrons are free to cycle around circular arrangements of atoms that are alternately single- and double-covalent bond, bonded to one another. This commonly seen model of aromatic rings, namely the idea that benzene was formed from a six-membered carbon ring with alternating single and double bonds (cyclohexatriene), was developed by Friedrich August Kekulé ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redox
Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. The oxidation and reduction processes occur simultaneously in the chemical reaction. There are two classes of redox reactions: * Electron transfer, Electron-transfer – Only one (usually) electron flows from the atom, ion, or molecule being oxidized to the atom, ion, or molecule that is reduced. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * Atom transfer – An atom transfers from one Substrate (chemistry), substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously, the oxidation state of oxygen decreases as it accepts electrons r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bleaching
Bleach is the generic name for any chemical product that is used industrially or domestically to remove color from (i.e. to whiten) fabric or fiber (in a process called bleaching) or to disinfect after cleaning. It often refers specifically to a dilute solution of sodium hypochlorite, also called "liquid bleach". Many bleaches have broad-spectrum bactericidal properties, making them useful for disinfecting and sterilizing. They are used in swimming pool sanitation to control bacteria, viruses, and algae and in many places where sterile conditions are required. They are also used in many industrial processes, notably in the bleaching of wood pulp. Bleaches also have other minor uses, like removing mildew, killing weeds, and increasing the longevity of cut flowers. Bleaches work by reacting with many colored organic compounds, such as natural pigments, and turning them into colorless ones. While most bleaches are oxidizing agents (chemicals that can remove electrons from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indigo Dye
Indigo dye is an organic compound with a distinctive indigo, blue color. Indigo is a natural dye obtained from the leaves of some plants of the Indigofera#Uses, ''Indigofera'' genus, in particular ''Indigofera tinctoria''. Dye-bearing ''Indigofera'' plants were once common throughout the world. It is now produced via chemical routes. Blue colorants are rare. Since indigo is insoluble, it is also referred to as a pigment (C.I. Pigment Blue 66, C.I.). Most indigo dye produced today is chemical synthesis, synthetic, constituting around 80,000 tonnes each year, as of 2023. It is most commonly associated with the production of denim cloth and jeans, blue jeans, where its properties allow for effects such as stone washing and stone washing#Acid-washed jeans, acid washing to be applied quickly. Uses The primary use for indigo is as a dye for cotton yarn, mainly used in the production of denim cloth suitable for blue jeans; on average, a pair of blue jeans requires to of dye. Smal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorine Dioxide
Chlorine dioxide is a chemical compound with the formula ClO2 that exists as yellowish-green gas above 11 °C, a reddish-brown liquid between 11 °C and −59 °C, and as bright orange crystals below −59 °C. It is usually handled as an aqueous solution. It is commonly used as a bleach. More recent developments have extended its applications in food processing and as a disinfectant. Structure and bonding The molecule ClO2 has an odd number of valence electrons, and therefore it is a Paramagnetism, paramagnetic radical (chemistry), radical. It is an unusual "example of an odd-electron molecule stable toward dimerization" (nitric oxide being another example). ClO2 crystallizes in the orthorhombic List of space groups, Pbca space group. History Chlorine dioxide was first prepared in 1811 by Sir Humphry Davy. In 1933, Lawrence O. Brockway, a graduate student of Linus Pauling, proposed a structure that involved a three-electron bond and two single bond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Celsius
The degree Celsius is the unit of temperature on the Celsius temperature scale "Celsius temperature scale, also called centigrade temperature scale, scale based on 0 ° for the melting point of water and 100 ° for the boiling point of water at 1 atm pressure." (originally known as the centigrade scale outside Sweden), one of two temperature scales used in the International System of Units (SI), the other being the closely related Kelvin scale. The degree Celsius (symbol: °C) can refer to a specific point on the Celsius temperature scale or to a difference or range between two temperatures. It is named after the Swedish astronomer Anders Celsius (1701–1744), who proposed the first version of it in 1742. The unit was called ''centigrade'' in several languages (from the Latin ''centum'', which means 100, and ''gradus'', which means steps) for many years. In 1948, the International Committee for Weights and Measures renamed it to honor Celsius and also to rem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
