Electrophilic substitution reactions are chemical reactions in which an electrophile displaces another group, typically but not always hydrogen. In Chemistry, an electrophile (literally electron-lover) is a Reagent attracted to Electrons that participates in a chemical reaction by accepting Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Electrophilic substitution is characteristic of aromatic compounds. Electrophilic aromatic substitution is an important way of introducing functional groups on benzene rings. Electrophilic aromatic substitution or EAS is an Organic reaction in which an atom usually Hydrogen, appended to an aromatic system is replaced Benzene, or benzol, is an organic Chemical compound and a known Carcinogen with the molecular formula C 6 H 6 The other main reaction type is electrophilic aliphatic substitution.

Contents 1 Electrophilic aromatic substitution 2 Electrophilic aliphatic substitution 3 See also 4 References

Electrophilic aromatic substitution

Main article: Electrophilic aromatic substitution

The most important reactions of this type that take place are aromatic nitration, aromatic halogenation, aromatic sulfonation and acylation and alkylating Friedel-Crafts reactions. Electrophilic aromatic substitution or EAS is an Organic reaction in which an atom usually Hydrogen, appended to an aromatic system is replaced Nitration is a general Chemical process for the introduction of a nitro group into a Chemical compound. In Organic chemistry, an electrophilic aromatic halogenation is a type of Electrophilic aromatic substitution. Aromatic sulfonation is an Organic reaction in which a hydrogen atom on an arene is replaced by a Sulfonic acid Functional group in an Electrophilic The Friedel-Crafts reactions are a set of reactions developed by Charles Friedel and James Crafts in 1877.

Electrophilic aliphatic substitution

In electrophilic substitution in aliphatic compounds, an electrophile displaces a functional group. In Organic chemistry, compounds composed of Carbon and Hydrogen are divided into two classes Aromatic compounds which contain Benzene rings In Chemistry, an electrophile (literally electron-lover) is a Reagent attracted to Electrons that participates in a chemical reaction by accepting In Organic chemistry, functional groups are specific groups of Atoms within Molecules that are responsible for the characteristic Chemical reactions This reaction is similar to nucleophilic aliphatic substitution where the reactant is a nucleophile rather than an electrophile. In organic and Inorganic chemistry, nucleophilic substitution is a fundamental class of Substitution reaction in which an "electron rich" In Chemistry, a nucleophile (literally nucleus lover as in nucleus and phile) is a Reagent that forms a Chemical bond to In Chemistry, an electrophile (literally electron-lover) is a Reagent attracted to Electrons that participates in a chemical reaction by accepting The two electrophilic reaction mechanisms, S_E1 and S_E2 (Substitution Electrophilic), are also similar to the nucleophile counterparts [[S_N1|SN1]] and [[S_N2|SN2]]. In the S_E1 course of action the substrate first ionizes into a carbanion and a positively charged organic residue. A carbanion is an Anion in which Carbon has an unshared pair of Electrons and bears a negative charge usually with three substituents for a total of eight The carbanion then quickly recombines with the electrophile. In Chemistry, an electrophile (literally electron-lover) is a Reagent attracted to Electrons that participates in a chemical reaction by accepting The S_E2 reaction mechanism has a single transition state in which the old bond and the newly formed bond are both present. The transition state of a Chemical reaction is a particular configuration along the Reaction coordinate.

Electrophilic aliphatic substitution reactions are:

• Nitrosation
• Ketone halogenation
• Keto-enol tautomerism
• aliphatic diazonium coupling
• carbene insertion into C-H bonds

See also

• Nucleophilic substitution

References

• March, Jerry (1985). Nitrosation is a process of converting organic compounds into Nitroso derivatives i In Organic chemistry ketone halogenation is a special type of Halogenation. In Organic chemistry, keto-enol Tautomerism refers to a Chemical equilibrium between a keto form (a Ketone or an Aldehyde In Chemistry, a carbene is a highly reactive Organic molecule containing a Carbon atom with six valence electrons and having the general formula In organic and Inorganic chemistry, nucleophilic substitution is a fundamental class of Substitution reaction in which an "electron rich" Advanced Organic Chemistry, 5th ed, Wiley.  

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