The key difference between methyl and methylene group is that the methyl group contains one carbon atom bonded to three hydrogen atoms whereas the methylene group contains one carbon atom bonded to two hydrogen atoms.
Methyl group and methylene group are important functional groups in organic molecules. These functional groups form from methane molecules. The chemical structure of the methyl group is CH3– while the chemical structure of the methylene group is CH2-.
CONTENTS
1. Overview and Key Difference
2. What is a Methyl Group
3. What is a Methylene Group
4. Side by Side Comparison – Methyl vs Methylene Group in Tabular Form
5. Summary
What is a Methyl Group?
Methyl group is a functional group in an organic compound, and it has the chemical formula CH3-. This functional group is derived from the methane molecule, CH4. We can abbreviate this group as “Me”. Furthermore, the methyl group contains one carbon atom bonded to three hydrogen atoms. Also, this is a hydrocarbon group that occurs in organic molecules. In most of the molecules, this is a very stable functional group.
Generally, the methyl group occurs as a part of a large organic compound. This functional group can exist in three different ways: as an anion, a cation or as a radical. The anion of the methyl group has eight valence electrons. The cation has six valence electrons, and the radical has seven valence electrons. However, all three forms are reactive and cannot be observed as individual species.
Figure 01: Methyl Group in Different Forms in Different Compounds
When considering their reactivity, it often tends to be unreactive. For example, methyl groups are not affected by even a strong acid when the methyl group is in an organic compound. However, its reactivity depends on the adjacent substituents. The oxidation of methyl groups is important in industrial applications. The products derived from methyl group oxidation include alcohol, aldehyde and carboxylic acid groups. For example, permanganate (a strong oxidant) can oxidize methyl group into a carboxylic acid group.
What is a Methylene Group?
Methylene group is a functional group in organic compounds and it has the chemical formula CH2-. As indicated by the chemical formula, this group has a carbon atom bonded to two hydrogen atoms. Generally, this functional group is abbreviated as CH2< because the methylene group can form two more covalent bonds that are represented by the < symbol.
Figure 02: A Methylene Group containing an Organic Compound
However, this group does not bind with the organic compound via a double bond; it only forms two single bonds. If there is a double bond, then we call this functional group as “methylidene group”.
What is the Difference Between Methyl and Methylene Group?
Methyl group and methylene group are important functional groups in organic molecules. The key difference between methyl and methylene group is that the methyl group contains one carbon atom bonded to three hydrogen atoms whereas the methylene group contains one carbon atom bonded to two hydrogen atoms. Moreover, the chemical structure of methyl group is CH3– and the chemical structure of methylene group is CH2-.
Below infographic summarizes the differences between methyl and methylene group.
Summary – Methyl vs Methylene Group
Methyl group and methylene group are important functional groups in organic molecules. The key difference between methyl and methylene group is that the methyl group contains one carbon atom bonded to three hydrogen atoms whereas the methylene group contains one carbon atom bonded to two hydrogen atoms.
Reference:
1. Helmenstine, Anne Marie. “Methyl Group Definition in Chemistry.” ThoughtCo, Feb. 11, 2020, Available here.
2. “Methyl Group.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 21 Nov. 2018, Available here.
Image Courtesy:
1. “Methyl Group General Formulae V” By Jü – Own work (Public Domain) via Commons Wikimedia
2. “1,6-diaminohexane-3D-balls” By Ben Mills – Own work (Public Domain) via Commons Wikimedia