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18 Ιουν 2012 · What are the factors that make a good nucleophile? For our purposes, there are at least four key factors contributing to nucleophilicity. Charge. Electronegativity. Solvent. Steric hindrance. The first two should hopefully be familiar from the discussion of what makes something a strong base.
20 Αυγ 2018 · What is Nucleophilic Aromatic Substitution and how does it differ from Electrophilic Aromatic Substitution? Let's look at some examples of both.
1 Ιαν 2014 · Nucleophilic compounds bearing thiol groups (-SH), primarily GSH and thioredoxin reduce electrophiles in S N 2 nucleophilic substitution reactions. The oxidized forms of the electron donors (usually disulfides), are then reduced back by hydride (H − ) transfer from NADPH.
Nucleophilic aromatic substitution occurs only if the aromatic ring has an electron-withdrawing substituent in a position ortho or para to the leaving group to stabilize the anion intermediate through resonance (Figure 16.19). A meta substituent offers no such resonance stabilization.
In addition, water, alcohols and thiols are nucleophilic, because they all have lone pairs that could be donated to an electrophile. Nitrogen also has a lone pair in most compounds. That means amines are good nucleophiles, too. Carbon does not normally have a lone pair, unless it is a carbanion.
An aromatic nucleophilic substitution in organic chemistry may simply be defined as a chemical reaction where the nucleophile displaces a good leaving group, such as a halide, on an aromatic ring. The aromatic nucleophilic substitution can primarily occur via three different routes as given below.
10 Ιουλ 2023 · Normally, aromatic rings are considered electron rich and are good nucleophiles in the classic electrophilic aromatic substitution (SEAr) reaction. There are three common ways of reversing this reactivity, and permitting the ring to be attacked by a nucleophile.
