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Thioformaldehyde
Thioformaldehyde is the organosulfur compound with the formula CH2S. It is the simplest thioaldehyde. This compound is not observed in the condensed state (solid or liquid) because it oligomerizes to 1,3,5-trithiane, which is a stable colorless compound with the same empirical formula. Despite the instability of these concentrated forms, thioformaldehyde as a dilute gas has been extensively studied. For these purposes, it is produced by thermal decomposition of dimethyl disulfide. The molecule has been observed in the interstellar medium and has attracted much attention for its fundamental nature. The tendency of thioformaldehyde to form chains and rings is a manifestation of the double bond rule In chemistry, the double bond rule states that elements with a principal quantum number (''n'') greater than 2 for their valence electrons ( period 3 elements and higher) tend not to form multiple bonds (e.g. double bonds and triple bonds). Do .... Although thioformaldehyde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thioaldehyde
In organic chemistry, a thial or thioaldehyde is a functional group which is similar to an aldehyde, , in which a sulfur (S) atom replaces the oxygen (O) atom of the aldehyde (R represents an alkyl or aryl group). Thioaldehydes are even more reactive than thioketones. Unhindered thioaldehydes are generally too reactive to be isolated — for example, thioformaldehyde, , condenses to the cyclic trimer 1,3,5-trithiane. Thioacrolein, , formed by decomposition of allicin from garlic, undergoes a self Diels-Alder reaction giving isomeric vinyldithiins. While thioformaldehyde is highly reactive, it is found in interstellar space along with its mono- and di-deuterated isotopologues. With sufficient steric bulk, however, stable thioaldehydes can be isolated. In early work, the existence of thioaldehydes was inferred by trapping processes. For instance the reaction of with benzaldehyde was proposed to form thiobenzaldehyde, which forms a cycloadduct with the dithiophosphine ylides to form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,3,5-trithiane
1,3,5-Trithiane is the chemical compound with the formula (CHS). This heterocycle is the cyclic trimer of the otherwise unstable species thioformaldehyde. It consists of a six-membered ring with alternating methylene bridges and thioether groups. It is prepared by treatment of formaldehyde with hydrogen sulfide. Trithiane is a building block molecule in organic synthesis, being a masked source of formaldehyde. In one application, it is deprotonated with organolithium reagents to give the lithium derivative, which can be alkylated. :(CHS) + RLi → (CHS)(CHLiS) + RH :(CHS)(CHLiS) + RBr → (CHS)(CHRS) + LiBr :(CHS)(CHRS) + HO → RCHO + .... Trithiane is the dithioacetal of formaldehyde. Other dithioacetals undergo similar reactions to the above. It is also a precursor to other organosulfur reagents. For example, chlorination in the presence of water affords the chloromethyl sulfonyl chloride: :(CHS) + 9 Cl + 6 HO → 3 ClCHSOCl + 12 HCl ... [...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] |
Oligomer
In chemistry and biochemistry, an oligomer () is a molecule that consists of a few repeating units which could be derived, actually or conceptually, from smaller molecules, monomers.Quote: ''Oligomer molecule: A molecule of intermediate relative molecular mass, the structure of which essentially comprises a small plurality of units derived, actually or conceptually, from molecules of lower relative molecular mass.'' The name is composed of Greek elements '' oligo-'', "a few" and '' -mer'', "parts". An adjective form is ''oligomeric''. The oligomer concept is contrasted to that of a polymer, which is usually understood to have a large number of units, possibly thousands or millions. However, there is no sharp distinction between these two concepts. One proposed criterion is whether the molecule's properties vary significantly with the removal of one or a few of the units. An oligomer with a specific number of units is referred to by the Greek prefix denoting that number, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethyl Disulfide
Dimethyl disulfide (DMDS) is an organic chemical compound with the molecular formula . It is a flammable liquid with an unpleasant, garlic-like odor resembling that of "leaking gas". The compound is colorless, although impure samples often appear yellowish. Occurrence and synthesis Dimethyl disulfide is widespread in nature. It is emitted by bacteria, fungi, plants, and animals. Along with dimethyl sulfide and dimethyl trisulfide, it has been confirmed as volatile compounds given off by the fly-attracting plant known as dead-horse arum (''Helicodiceros muscivorus''). These flies are attracted to the odor resembling that of fetid meat, and thus help pollinate this plant. The James Webb Space Telescope has possibly detected evidence of DMDS in the atmosphere of the exoplanet K2-18b. DMDS can be produced by the oxidation of methanethiol, e.g. with iodine: : Chemical reactions Important reactions include chlorination giving methanesulfenyl chloride (), methanesulfinyl chloride ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interstellar Medium
The interstellar medium (ISM) is the matter and radiation that exists in the outer space, space between the star systems in a galaxy. This matter includes gas in ionic, atomic, and molecular form, as well as cosmic dust, dust and cosmic rays. It fills interstellar space and blends smoothly into the surrounding intergalactic medium. The energy that occupies the same volume, in the form of electromagnetic radiation, is the interstellar radiation field. Although the density of atoms in the ISM is usually far below that in the best laboratory vacuums, the mean free path between collisions is short compared to typical interstellar lengths, so on these scales the ISM behaves as a gas (more precisely, as a Plasma (physics), plasma: it is everywhere at least slightly ionized), responding to pressure forces, and not as a collection of non-interacting particles. The interstellar medium is composed of multiple phases distinguished by whether matter is ionic, atomic, or molecular, and the temp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double Bond Rule
In chemistry, the double bond rule states that elements with a principal quantum number (''n'') greater than 2 for their valence electrons ( period 3 elements and higher) tend not to form multiple bonds (e.g. double bonds and triple bonds). Double bonds for these heavier elements, when they exist, are often weak due to poor orbital overlap between the ''n''>2 orbitals of the two atoms. Although such compounds are not intrinsically unstable, they instead tend to dimerize or even polymerize In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many form .... Moreover, the multiple bonds of the elements with ''n''=2 are much stronger than usual, because lone pair repulsion weakens their sigma bonding but not their pi bonding. An example is the rapid polymerization that occurs upon condensation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WSCH2
WSCH (99.3 FM) is a radio station broadcasting a Country format. It is licensed to Aurora, Indiana Aurora is a city in Dearborn County, Indiana, United States. The population was 3,479 at the 2020 census. Geography According to the 2010 census, Aurora has a total area of , of which (or 89.41%) is land and (or 10.59%) is water. History Aur ..., United States, and serves the Cincinnati area. The station is owned by Wagon Wheel Broadcasting, LLC. External links * SCH {{Indiana-radio-station-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
