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Acetic anhydride in a glass bottle. Acetic anhydride, like most acid anhydrides, is a flexible molecule with a nonplanar structure. [4] The pi system linkage through the central oxygen offers very weak resonance stabilization compared to the dipole-dipole repulsion between the two carbonyl oxygens. The energy barriers to bond rotation between ...
The product of the condensation of two molecules of acetic acid is acetic anhydride. The worldwide production of acetic anhydride is a major application, and uses approximately 25% to 30% of the global production of acetic acid. The main process involves dehydration of acetic acid to give ketene at 700–750 °C. Ketene is thereafter reacted ...
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 ...
As examples, a water molecule easily adds to ketene to give 1,1-dihydroxyethene and acetic anhydride is produced by the reaction of acetic acid with ketene. Reactions between diols (HO−R−OH) and bis-ketenes (O=C=CH−R'−CH=C=O) yield polyesters with a repeat unit of (−O−R−O−CO−R'−CO).
Melt condensation polymerization involves reacting dicarboxylic acid monomers with excess acetic anhydride at a high temperature and under a vacuum to form the polymers. Catalysts may be used to achieve higher molecular weights and shorter reaction times. Generally, a one-step synthesis (method involving only one reaction) is used which does ...
Mixture of nitric and acetic acids or nitric acid and acetic anhydride is commercially important in the production of RDX, as amines are destructed by sulfuric acid. Acetyl nitrate had also been used as a nitration agent. [14] [15] In the Wolffenstein–Böters reaction, benzene reacts with nitric acid and mercury(II) nitrate to give picric acid.
Propanoic acid 0.993 Water 1.000 2-Methoxyethyl acetate 1.009 Benzonitrile 1.01 1-Methyl-2-pyrrolidinone 1.028 Hexamethylphosphoramide 1.03 1,4-Dioxane 1.033 Acetic acid 1.049 Acetic anhydride 1.08 Dimethyl sulfoxide 1.092 Chlorobenzene 1.1066 Deuterium oxide 1.107 Ethylene glycol 1.115 Diethylene glycol 1.118 Propylene carbonate 1.21 Formic acid