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The synthesis of methyl benzoate by Fischer–Speier esterification. Fischer esterification or Fischer–Speier esterification is a special type of esterification by refluxing a carboxylic acid and an alcohol in the presence of an acid catalyst. The reaction was first described by Emil Fischer and Arthur Speier in 1895. [1]
The classic example of a dehydration reaction is the Fischer esterification, which involves treating a carboxylic acid with an alcohol to give an ester RCO 2 H + R′OH ⇌ RCO 2 R′ + H 2 O. Often such reactions require the presence of a dehydrating agent, i.e. a substance that reacts with water.
Fischer glycosidation (or Fischer glycosylation) refers to the formation of a glycoside by the reaction of an aldose or ketose with an alcohol in the presence of an acid catalyst. The reaction is named after the German chemist, Emil Fischer, winner of the Nobel Prize in chemistry, 1902, who developed this method between 1893 and 1895. [1] [2] [3]
In acid-catalyzed Fischer esterification, the proton binds to oxygens and functions as a Lewis acid to activate the ester carbonyl (top row) as an electrophile, and converts the hydroxyl into the good leaving group water (bottom left). Both lower the kinetic barrier and speed up the attainment of chemical equilibrium.
All of the processes of Shiina macrolactonization consist of reversible reactions, with the exception of the last cyclization step.At the first stage of the reaction, mixed anhydride (MA) is produced quickly under mild conditions; at the second stage, a faster cyclization of the MA prevents an increase in MA concentration.
The analogous alkylation of an acetate salt is rarely practiced. The alkylation can be conducted using Mannich bases and the thiocarboxylic acid: CH 3 COSH + R' 2 NCH 2 OH → CH 3 COSCH 2 NR' 2 + H 2 O. Thioesters can be prepared by condensation of thiols and carboxylic acids in the presence of dehydrating agents: [2] [3] RSH + R'CO 2 H → ...
Octyl acetate, or octyl ethanoate, is an organic compound with the formula CH 3 (CH 2) 7 O 2 CCH 3.It is classified as an ester that is formed from 1-octanol (octyl alcohol) and acetic acid.
TCFH itself is a common reagent used in the preparation of uronium and guanidinium salts used for amide bond formation and peptide synthesis, such as HATU. [3] [4] [5]Amide bond formation with TCFH can be performed in a wide range of organic solvents, most commonly acetonitrile, but also water [6] and in the solid state. [7]