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Acyl compounds react with nucleophiles via an addition mechanism: the nucleophile attacks the carbonyl carbon, forming a tetrahedral intermediate. This reaction can be accelerated by acidic conditions, which make the carbonyl more electrophilic , or basic conditions, which provide a more anionic and therefore more reactive nucleophile.
This type of reaction is also called a 1,2-nucleophilic addition. The stereochemistry of this type of nucleophilic attack is not an issue, when both alkyl substituents are dissimilar and there are not any other controlling issues such as chelation with a Lewis acid, the reaction product is a racemate. Addition reactions of this type are numerous.
Carboxypeptidases act by replacing the substrate water with a carbonyl (C=O) group. The carboxypeptidase A hydrolysis reaction has two mechanistic hypotheses, via a nucleophilic water and via an anhydride. In the first proposed mechanism, a promoted-water pathway is favoured as Glu270 deprotonates the nucleophilic water.
In organic chemistry, an active ester is an ester functional group that is highly susceptible toward nucleophilic attack. Activation can be imparted by modifications of the acyl or the alkoxy components of a normal ester, say ethyl acetate. Typical modifications call for electronegative substituents.
The mechanism of the Michaelis–Arbuzov reaction. The Michaelis–Arbuzov reaction is initiated with the S N 2 attack of the nucleophilic phosphorus species (1 - A phosphite) with the electrophilic alkyl halide (2) to give a phosphonium salt as an intermediate (3).
Carbocupration is a nucleophilic addition of organocopper reagents (R−Cu) to acetylene or terminal alkynes resulting in an alkenylcopper compound (R 2 C=C(R)−Cu). [17] It is a special case of carbometalation and also called the Normant reaction. [18] [19] Catalytic cycle for carbocupration for the synthesis of aldol, Baylis-Hillman type ...
While everyone lost weight during the study period, the researchers discovered that those who added more protein and fiber to their diets lost the most—up to 9.6 percent of their original body ...
Incoming nucleophilic attack happens at one of the termini of the π-system in the figure below: In this example the ring system can be thought of as analogous to 1,3-butadiene. Following the Green–Davies–Mingos rules, since butadiene is an open π-ligand of even hapticity, nucleophilic attack will occur at one of the terminal positions of ...