The key difference between hyperconjugation and inductive effect is that hyperconjugation explains the interaction between sigma bonds and pi bonds whereas inductive effect explains the transmission of an electrical charge through a chain of atoms.
Both terms hyperconjugation and inductive effect are electronic effects in organic compounds that lead to the stabilization of the compound.
CONTENTS
1. Overview and Key Difference
2. What is Hyperconjugation
3. What is Inductive Effect
4. Side by Side Comparison – Hyperconjugation vs Inductive Effect in Tabular Form
5. Summary
What is Hyperconjugation?
Hyperconjugation is the interaction of σ-bonds with a pi bond network. In this concept, we say the electrons in a sigma bond undergo an interaction with an adjacent partially (or completely) filled p orbital, or with a pi orbital. This process takes place in order to increase the stability of a molecule.
Figure 01: An Example of a Hyperconjugation Process
The cause for hyperconjugation is the overlap of bonding electrons in C-H sigma bond with a p orbital or a pi orbital of the adjacent carbon atom. Here, the hydrogen atom resides in close proximity as a proton. The negative charge that develops on the carbon atom undergoes delocalization due to the overlap of p orbital or pi orbital. Furthermore, there are several effects of hyperconjugation on chemical properties of compounds. i.e. in carbocation, hyperconjugation causes the positive charge on the carbon atom.
What is Inductive Effect?
Inductive effect is an effect caused by the transmission of an electrical charge throughout a chain of atoms. This transmission of the charge finally leads to a fixed electrical charge on atoms. This effect occurs due to the differences in the electronegative values of atoms of a molecule.
An atom with a higher electronegativity tends to attract electrons towards themselves than lower electronegative atoms. Therefore, when a highly electronegative atom and a low electronegative atom are in a covalent bond, the bond electrons are attracted towards the highly electronegative atom. This induces the low electronegative atom to get a partially positive charge. The highly electronegative atom will get a partial negative charge. We call this bond polarization.
The inductive effect occurs in two ways as follows.
Electron Releasing
This effect is seen when groups like alkyl groups are attached to a molecule. These groups are less electron-withdrawing and tend to give electrons to the rest of the molecule.
Electron Withdrawing
This arises when a highly electronegative atom or a group is attached to a molecule. This atom or group will attract electrons from the rest of the molecule.
Moreover, the inductive effect has a direct effect on the stability of molecules, especially organic molecules. If a carbon atom has a partial positive charge, an electron releasing group such as an alkyl group can reduce or remove this partial positive charge by providing electrons. Then the stability of that molecule increases.
What is the Difference Between Hyperconjugation and Inductive Effect?
The key difference between hyperconjugation and inductive effect is that hyperconjugation explains the interaction between sigma bonds and pi bonds whereas inductive effect explains the transmission of an electrical charge through a chain of atoms. Hyperconjugation stabilizes the molecule through pi-electron delocalization while inductive effect stabilizes the molecule via transmission of electrical charges through the molecule.
Summary – Hyperconjugation vs Inductive Effect
The key difference between hyperconjugation and inductive effect is that hyperconjugation explains the interaction between sigma bonds and pi bonds whereas inductive effect explains the transmission of an electrical charge through a chain of atoms.
Reference:
1. Helmenstine, Anne Marie. “Inductive Effect & Resonance.” ThoughtCo, Jul. 3, 2019, thoughtco.com/definition-of-inductive-effect-605241.
Image Courtesy:
1. “THPOH-hyperconjugation” By English Wikipedia user Dmacks (CC BY-SA 3.0) via Commons Wikimedia
2. “Inductive effect trends” By Manishearth at the English language Wikipedia (CC BY-SA 3.0) via Commons Wikimedia