Inductive effect

Organic compounds mainly consist of covalent bonds. The displacements of the electron pairs in these covalent bonds may take place either on their own or under the influence of other species. Three types of electron displacements are generally noticed in the mechanism of organic reactions.

Inductive Effect

Whenever the withdrawing electron group (such as halogen) is attached to the end of a carbon chain, a permanent effect called inductive effect takes place. To understand this, consider a chain of carbon atoms having Cl atom at one end: C-C-C-C-Cl

Since chlorine (Cl) is more electronegative than C, the electron pair shared between C, and Cl is displaced towards the Cl atom, due its larger electronegativity. A partial negative charge (d-) is thus acquired by Cl and C acquires a partial positive charge (d+). The displacement is, not limited to C₁-Cl bond but is transmitted to other carbons along the chain. This happens due to the small positive charge on C, which attracts the of electrons of C₁-C₂ bond towards it. This displacement results in the positive charge on C₁ being partially neutralized while a small positive charge is developed on C₂. The charge on C₂ is less than that on C₁ (d'+ < d+).

Similarly, C₃ will acquire a small positive charge d +"<d+" < d+').