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Monday, September 13, 2021

09-13-2021-0041 - cordite

 Acyloins or Î±-hydroxy ketones[1] are a class of organic compounds which all possess a hydroxy group adjacent to a ketone group. The named acyloin is derived from the fact that they are formally derived from reductive coupling of carboxylic acyl groups.[2]

The structure of a typical acyloin.

https://en.wikipedia.org/wiki/Acyloin

The Rubottom oxidation is a useful, high-yielding chemical reaction between  silyl enol ethers and peroxyacids to give the corresponding α-hydroxy carbonyl product.[1][2][3][4][5] The mechanism of the reaction was proposed in its original disclosure by A.G. Brook[6][7] with further evidence later supplied by George M. Rubottom.[8] After a Prilezhaev-type oxidation of the silyl enol ether with the peroxyacid to form the siloxy oxirane intermediate, acid-catalyzed ring-opening yields an oxocarbenium ion.[1][4] This intermediate then participates in a 1,4-silyl migration (Brook rearrangement) to give an α-siloxy carbonyl derivative that can be readily converted to the α-hydroxy carbonyl compound in the presence of acid, base, or a fluoride source.[1][9][10]

https://en.wikipedia.org/wiki/Rubottom_oxidation

Mesoxalic acid, also called oxomalonic acid or ketomalonic acid, is an organic compound with formula C3H2O5 or HO−(C=O)3−OH.

Mesoxalic acid is both a dicarboxylic acid and a ketonic acid. It readily loses two protons to yield the divalent anion C
3
O2−
5
, called mesoxalateoxomalonate, or ketomalonate. These terms are also used for salts containing this anion, such as sodium mesoxalate, Na2C3O5; and for esters containing the −C3O5− or −O−(C=O)3−O− moiety, such as diethyl mesoxalate, (C2H5)2C3O5. Mesoxalate is one of the oxocarbon anions, which (like carbonate CO2−
3
 and oxalate C
2
O2−
4
) consist solely of carbon and oxygen.

Mesoxalic acid readily absorbs and reacts with water to form a product commonly called "mesoxalic acid monohydrate", more properly dihydroxymalonic acid, HO−(C=O)−C(OH)2−(C=O)−OH.[2] In product catalogs and other contexts, the terms "mesoxalic acid", "oxomalonic acid" and so on often refer to this "hydrated" compound. In particular, the product traded as "sodium mesoxalate monohydrate" is almost always sodium dihydroxymalonate.

Mesoxalic acid hydration equilibrium.svg

https://en.wikipedia.org/wiki/Mesoxalic_acid


Cordite is a family of smokeless propellants developed and produced in the United Kingdom since 1889 to replace gunpowder as a military propellant. Like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance. These produce a subsonic deflagration wave rather than the supersonic detonation wave produced by brisants, or high explosives. The hot gases produced by burning gunpowder or cordite generate sufficient pressure to propel a bullet or shell to its target, but not so quickly as to routinely destroy the barrel of the gun.

Cordite was used initially in the .303 British, Mark I and II, standard rifle cartridge between 1891 and 1915; shortages of cordite in World War I led to the creation of the ‘Devils Porridge’ munitions factory on the English-Scottish border, (producing 800 tonnes of cordite per annum). The UK also imported some United States–developed smokeless powders for use in rifle cartridges. Cordite was also used for large weapons, such as tank gunsartillery, and naval guns. It has been used mainly for this purpose since the late 19th century by the UK and British Commonwealth countries. Its use was further developed before World War II, and as 2-and-3-inch-diameter (51 and 76 mm) Unrotated Projectilesfor launching anti-aircraft weapons.[1] Small cordite rocket charges were also developed for ejector seats made by the Martin-Baker Company. Cordite was also used in the detonation system of the Little Boy atomic bomb dropped over Hiroshima in August 1945.[citation needed]

The term "cordite" generally disappeared from official publications between the wars. During World War II, double-base propellants were very widely used, and there was some use of triple-base propellants by artillery. Triple-base propellants were used in post-war ammunition designs and remain in production for UK weapons; most double-base propellants left service as World War II stocks were expended after the war. For small arms it has been replaced by other propellants, such as the Improved Military Rifle (IMR)line of extruded powder or the WC844 ball propellant currently in use in the 5.56×45mm NATO.[2] Production ceased in the United Kingdom around the end of the 20th century, with the closure of the last of the World War II cordite factories, ROF Bishopton. Triple-base propellant for UK service (for example, the 105 mm L118 Light Gun) is now manufactured in Germany.

Replacements for gunpowder (black powder)[edit]

Gunpowder, an explosive mixture of sulfurcharcoal and potassium nitrate (also known as saltpeter), was the original propellant employed in firearms and fireworks. It was used from about the 10th or 11th century onwards, but it had disadvantages, including the large quantity of smoke it produced. With the 19th-century development of various "nitro explosives", based on the reaction of nitric acid mixtures on materials such as cellulose and glycerine, a search began for a replacement for gunpowder.[3]

https://en.wikipedia.org/wiki/Cordite


BIOFUEL

https://en.wikipedia.org/wiki/Glycerol

https://en.wikipedia.org/wiki/Glycerol#Chemical_intermediate


https://en.wikipedia.org/wiki/Category:Glassforming_liquids_and_melts


Chemical structure of HMPA

https://en.wikipedia.org/wiki/Hexamethylphosphoramide

https://en.wikipedia.org/wiki/Dimethyl_sulfoxide


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