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Used in a more general sense, the term X,Y-acetal also refers to any functional group that consists of a carbon bearing two heteroatoms X and Y. For example, N,O-acetal refers to compounds of type R 1 R 2 C(OR)(NR' 2) (R,R' ≠ H) also known as a hemiaminal ether or Aminal, a.k.a. aminoacetal.
Aldehydes and to some extent even ketones, hydrate to geminal diols. The reaction is especially dominant for formaldehyde, which, in the presence of water, exists significantly as dihydroxymethane. Conceptually similar reactions include hydroamination and hydroalkoxylation, which involve adding amines and alcohols to alkenes.
The example below depicts the acetalisation reaction of D-ribose 1. With acetone or 2,2-dimethoxypropane as the acetalisation reagent the reaction is under thermodynamic reaction control and results in the pentose 2. The latter reagent in itself is an acetal and therefore the reaction is actually a cross-acetalisation.
Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, [11] and is produced by plants. It is also produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase and is a contributing cause of hangover after alcohol consumption. [ 12 ]
Hygroscopic bi-layered cell arrays act as a capitulum hinge in some plants, Xerochrysum bracteatum and Syngonanthus elegans being examples. The hygroscopic bending of involucral bracts surrounding a capitulum contributes to flower protection and pollination [ 21 ] and assists dispersion by protecting delicate pappi filaments from entanglement ...
Piperonal can be prepared by the oxidative cleavage of isosafrole or by using a multistep sequence from catechol or 1,2-methylenedioxybenzene.Synthesis from the latter chemical is accomplished through a condensation reaction with glyoxylic acid followed by cleaving the resulting α-hydroxy acid with an oxidizing agent.
In addition, acetyl-CoA is a precursor for the biosynthesis of various acetyl-chemicals, acting as an intermediate to transfer an acetyl group during the biosynthesis of those acetyl-chemicals. Acetyl-CoA is also involved in the regulation of various cellular mechanisms by providing acetyl groups to target amino acid residues for post ...
For example: ethanol, CH 3 −CH 2 −OH, is the product of the hydration reaction of ethene, CH 2 =CH 2, formed by the addition of H to one C and OH to the other C, and so can be considered as the hydrate of ethene. A molecule of water may be eliminated, for example, by the action of sulfuric acid.