Organic Chemistry/Introduction to reactions/Electrophilic additions

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Electrophilic additions are also referred to as addition reactions.

An addition

CH2=CH2 + HX → CH3-CH2X

Its reverse, an elimination

CH3-CH2X + base, Δ → CH2=CH2

Electrophilic additions are essentially the reverse of an E1 elimination reaction, sometimes exactly the microscopic reverse.

Microscopic reverse

This means that the mechanism of the reaction follows each and every step of the related reaction in reverse order, without deviation. Sometimes, a reaction can be reversed but using a different series of tiny steps. When that happens, it is NOT called a microscopic reverse.

Addition reactions involve carbocations. This intermediate carbocation can rearrange.

Addition reactions follow Markovnikov's rule. (The higher priority substituent adds to the more highly substituted carbon of the carbon-carbon double bond).

(Series of sample reactions here)