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Acetylated wood is a type of modified wood that is produced through a chemical modification process. [1] It produced from a chemical reaction (named as acetylation), involving acetic anhydride and a modification process to make wood highly resistant to biological attacks by fungi and wood-boring insects and durable to environmental conditions.
Cellulose is a polyol and thus susceptible to acetylation, which is achieved using acetic anhydride. Acetylation disrupts hydrogen bonding, which otherwise dominates the properties of cellulose. Consequently, the cellulose esters are soluble in organic solvents and can be cast into fibers and films. [12]
Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula (CH 3 CO) 2 O. Commonly abbreviated Ac 2 O , it is the simplest isolable anhydride of a carboxylic acid and is widely used as a reagent in organic synthesis .
For example, Friedel–Crafts acylation uses acetyl chloride (CH 3 COCl) as the agent and aluminum chloride (AlCl 3) as a catalyst to add an acetyl group to benzene: [2] Friedel-Crafts acylation of benzene by ethanoyl chloride. This reaction is an example of electrophilic aromatic substitution.
The Nencki reaction (1881) is the ring acetylation of phenols with acids in the presence of zinc chloride. [24] In a green chemistry variation aluminium chloride is replaced by graphite in an alkylation of p-xylene with 2-bromobutane. This variation will not work with primary halides from which less carbocation involvement is inferred. [25]
The analytical method used to determine hydroxyl value traditionally involves acetylation of the free hydroxyl groups of the substance with acetic anhydride in pyridine solvent. After completion of the reaction, water is added, and the remaining unreacted acetic anhydride is converted to acetic acid and measured by titration with potassium ...
A common type of organic acid anhydride is a carboxylic anhydride, where the parent acid is a carboxylic acid, the formula of the anhydride being (RC(O)) 2 O. Symmetrical acid anhydrides of this type are named by replacing the word acid in the name of the parent carboxylic acid by the word anhydride. [2] Thus, (CH 3 CO) 2 O is called acetic ...
Enzymes which perform acetylation on proteins or other biomolecules are known as acetyltransferases. In biological organisms, acetyl groups are commonly transferred from acetyl-CoA to other organic molecules. Acetyl-CoA is an intermediate in the biological synthesis and in the breakdown of many organic molecules.