Why do alkenes undergo electrophilic addition?

Alkenes undergo electrophilic addition due to the high electron density of their carbon-carbon double bond, which attracts electrophiles.

Alkenes are hydrocarbons that contain a carbon-carbon double bond. This double bond is composed of a sigma bond and a pi bond. The pi bond, formed by the sideways overlap of p orbitals, is located above and below the plane of the molecule. This results in an area of high electron density, making the double bond a region of negative charge. This negative charge attracts electrophiles, which are electron-deficient species.

Electrophilic addition is a common reaction of alkenes. In this reaction, an electrophile is attracted to the electron-rich double bond of the alkene. The electrophile accepts a pair of electrons from the double bond, forming a new bond with one of the carbon atoms. This breaks the pi bond and leaves a positively charged carbon atom, known as a carbocation. The carbocation is then attacked by a nucleophile, which donates a pair of electrons to form a new bond. This results in the addition of two new groups across the double bond.

The electrophilic addition reaction is a key reaction in organic chemistry, as it allows for the formation of a wide range of products from simple alkene starting materials. The nature of the electrophile and the nucleophile, as well as the conditions of the reaction, can be varied to produce different products. This makes electrophilic addition a versatile and important reaction for the synthesis of complex organic molecules.

In summary, the high electron density of the carbon-carbon double bond in alkenes makes them attractive to electrophiles. This leads to electrophilic addition reactions, where an electrophile and a nucleophile add across the double bond. These reactions are a fundamental part of organic chemistry, allowing for the synthesis of a wide range of products from simple alkene starting materials.