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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.
Condensation reactions likely played major roles in the synthesis of the first biotic molecules including early peptides and nucleic acids. In fact, condensation reactions would be required at multiple steps in RNA oligomerization: the condensation of nucleobases and sugars, nucleoside phosphorylation, and nucleotide polymerization. [6]
Since the Lewis acid catalyst is reproduced at the end of the reaction, only a small proportion of catalyst is needed relative to the starting material to drive the reaction forward. In the basic reaction, 2-methyl-6-nitrobenzoic anhydride is primarily used as a dehydration condensation agent. [5]
An aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties (of aldehydes or ketones) react to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction), and this is then followed by dehydration to give a conjugated enone.
Because of the removal of the water molecule from the product, the term of convenience for such a process is "dehydration reaction" (also "condensation reaction" or "dehydration synthesis"). For example, milk sugar (lactose) is a disaccharide made by condensation of one molecule of each of the monosaccharides glucose and galactose, whereas the ...
Examples include solvent dehydration: dehydrating the ethanol/water and isopropanol/water azeotropes, continuous ethanol removal from yeast fermentors, continuous water removal from condensation reactions such as esterifications to enhance conversion and rate of the reaction, membrane introduction mass spectrometry, removing organic solvents ...
The first example of an enantioselective nitroaldol reaction was reported in 1992 using Shibasaki catalysts. [11] One of the most frequently employed methods for inducing enantio- or diastereoselectivity in the Henry reaction is the use of chiral metal catalysts, in which the nitro group and carbonyl oxygen coordinate to a metal that is bound ...
Generic hydrolysis reaction. (The 2-way yield symbol indicates a chemical equilibrium in which hydrolysis and condensation are reversible.). Hydrolysis (/ h aɪ ˈ d r ɒ l ɪ s ɪ s /; from Ancient Greek hydro- 'water' and lysis 'to unbind') is any chemical reaction in which a molecule of water breaks one or more chemical bonds.