Search results
Results From The WOW.Com Content Network
Alkaline hydrolysis of esters is also known as saponification. A base such as sodium hydroxide is required in stochiometric amounts. Unlike acid-catalyzed ester hydrolysis, it is not an equilibrium reaction and proceeds to completion. Hydroxide ion attacks the carbonyl carbon to give a tetrahedral intermediate, which then expels an alkoxide ion.
[1] [2] In organic chemistry, ether cleavage is an acid catalyzed nucleophilic substitution reaction. Depending on the specific ether, cleavage can follow either S N 1 or S N 2 mechanisms. Distinguishing between both mechanisms requires consideration of inductive and mesomeric effects that could stabilize or destabilize a potential carbocation ...
Saponification is a process of cleaving esters into carboxylate salts and alcohols by the action of aqueous alkali. Typically aqueous sodium hydroxide solutions are used. [1] [2] It is an important type of alkaline hydrolysis. When the carboxylate is long chain, its salt is called a soap. The saponification of ethyl acetate gives sodium acetate ...
Acid–base-catalysed hydrolyses are very common; one example is the hydrolysis of amides or esters. Their hydrolysis occurs when the nucleophile (a nucleus-seeking agent, e.g., water or hydroxyl ion) attacks the carbon of the carbonyl group of the ester or amide. In an aqueous base, hydroxyl ions are better nucleophiles than polar molecules ...
Asymmetric ester hydrolysis with pig liver esterase is the enantioselective conversion of an ester to a carboxylic acid through the action of the enzyme pig liver esterase (EC 3.1.1.1). Asymmetric ester hydrolysis involves the selective reaction of one of a pair of either enantiotopic (within the same molecule and related by a symmetry plane of ...
Scheme 2. Hydrolysis of benzoic acid esters. Reaction constants are known for many other reactions and equilibria. Here is a selection of those provided by Hammett himself (with their values in parentheses): the hydrolysis of substituted cinnamic acid ester in ethanol/water (+1.267) the ionization of substituted phenols in water (+2.008)
Transesterification is the process of exchanging the organic functional group R″ of an ester with the organic group R' of an alcohol. These reactions are often catalyzed by the addition of an acid or base catalyst. [1] Strong acids catalyze the reaction by donating a proton to the carbonyl group, thus making it a more potent electrophile.
Ortho esters are readily hydrolyzed in mild aqueous acid to form esters: . RC(OR ′) 3 + H 2 O → RCO 2 R ′ + 2 R ′ OH. For example, trimethyl orthoformate CH(OCH 3) 3 may be hydrolyzed (under acidic conditions) to methyl formate and methanol; [5] and may be further hydrolyzed (under alkaline conditions) to salts of formic acid and methanol.