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Ethylene glycol (IUPAC name: ethane-1,2-diol) is an organic compound (a vicinal diol [7]) with the formula (CH 2 OH) 2. It is mainly used for two purposes: as a raw material in the manufacture of polyester fibers and for antifreeze formulations. It is an odorless, colorless, flammable, viscous liquid.
Although the classic substrate for the Criegee oxidation are 1,2-diols, the oxidation can be employed with β-amino alcohols, [10] α-hydroxy carbonyls, [11] and α-keto acids, [12] In the case of β-amino alcohols, a free radical mechanism is proposed. The Criegee oxidation can also be employed with 2,3-epoxy alcohols forms α-acetoxy carbonyls.
At time of harvest, there is usually an equal amount of glucose and fructose molecules in the grape; however, as the grape overripens the level of fructose will become higher. In wine, fructose can taste nearly twice as sweet as glucose and is a key component in the creation of sweet dessert wines. During fermentation, glucose is consumed first ...
Micro-oxygenation is a process used in winemaking to introduce oxygen into wine in a controlled manner. Developed in 1991 by Patrick DuCournau , working with the exceptionally tannic grape Tannat in Madiran , the process gained usage in modern winemaking following the 1996 authorization by the European Commission .
Esters: [2] Ethyl acetate is the most common ester in wine, being the product of the most common volatile organic acid — acetic acid, and the ethyl alcohol generated during the fermentation. Norisoprenoids , such as C13-norisoprenoids found in grape ( Vitis vinifera ) [ 8 ] or wine , [ 9 ] can be produced by fungal peroxidases [ 10 ] or ...
The oxidation of primary alcohols to carboxylic acids normally proceeds via the corresponding aldehyde, which is transformed via an aldehyde hydrate (gem-diol, R-CH(OH) 2) by reaction with water. Thus, the oxidation of a primary alcohol at the aldehyde level without further oxidation to the carboxylic acid is possible by performing the reaction ...
In a vicinal diol, the two hydroxyl groups occupy vicinal positions, that is, they are attached to adjacent atoms. These compounds are called glycols [5] (though the term can be used more widely). Examples include ethane-1,2-diol or ethylene glycol HO−(CH 2) 2 −OH, a common ingredient of antifreeze products.
Glyoxal was first prepared and named by the German-British chemist Heinrich Debus (1824–1915) by reacting ethanol with nitric acid. [4] [5]Commercial glyoxal is prepared either by the gas-phase oxidation of ethylene glycol in the presence of a silver or copper catalyst (the Laporte process) or by the liquid-phase oxidation of acetaldehyde with nitric acid.