The key difference between suprafacial and antarafacial is that the term suprafacial refers to the relationship between two simultaneous chemical bonds making and/or breaking processes in the same face of a pi system or in an isolated orbital, whereas the term antarafacial refers to the same relationship in opposite faces of a pi system or an isolated orbital.
The terms suprafacial and antarafacial are useful concepts in organic chemistry, and these terms describe the relationship between two simultaneous processes: chemical bond making and/or bond breaking at a reaction center. This reaction center can be a conjugated/pi system, a p orbital, an sp orbital, or a sigma bond.
CONTENTS
1. Overview and Key Difference
2. What is Suprafacial
3. What is Antarafacial
4. Suprafacial and Antarafacial in Tabular Form
5. Summary – Suprafacial vs Antarafacial
What is Suprafacial?
A suprafacial state is when the relationship between chemical bond making and/or bond breaking processes at a reaction center occurs at the same face at the reaction center. This state is abbreviated as “s”. When considering a sigma bond, the suprafacial state corresponds to the occasion where two interior lobes or two exterior lobes of the bond are involving in these processes.
What is Antarafacial?
An antarafacial state is when the relationship between chemical bond making and/or bond breaking processes at a reaction center occurs at the opposite faces at the reaction center. This state is abbreviated as “a”. When considering a sigma bond, the suprafacial state corresponds to the occasion where one interior lobe and one exterior lobe of the bond is involving in these processes.
Figure 01: Description of Suprafacial and Antarafacial Chemical Concepts
The terms suprafacial and antarafacial are useful concepts in organic chemistry, and these terms describe the relationship between two simultaneous processes of chemical bond formation and break down.
What is the Difference Between Suprafacial and Antarafacial?
A suprafacial state is when the relationship between chemical bond making and/or bond breaking processes at a reaction center occur at the same face at the reaction center, while an antarafacial state is when the relationship between chemical bond making and/or bond breaking processes at a reaction center occur at the opposite faces at the reaction center. Therefore, the key difference between suprafacial and antarafacial is that the term suprafacial refers to the relationship between two simultaneous chemical bond making and/or breaking processes in the same face of the pi system or in isolated orbital, whereas antarafacial refers to the same relationship in opposite faces of a pi system or an isolated orbital. We can abbreviate suprafacial state as “s” and antarafacial state as “a”.
Suprafacial corresponds to the occasion where one interior lobe and one exterior lobe of the bond is involving in these processes, whereas antarafacial corresponds to the occasion where one interior lobe and one exterior lobe of the bond is involving in these processes.
The below infographic lists the differences between suprafacial and antarafacial in tabular form for side by side comparison.
Summary – Suprafacial vs Antarafacial
The terms suprafacial and antarafacial are very important in organic chemistry in describing the properties of bond making and bond breaking processes. The key difference between suprafacial and antarafacial is that the term suprafacial refers to the relationship between two simultaneous chemical bond making and/or breaking processes in the same face of the pi system or in isolated orbital, whereas the term antarafacial refers to the same relationship in opposite faces of the pi system or the isolated orbital.
Reference:
1. Ghosh, P. “What Is Sigmatropic Rearrangement and What Is Suprafacial and Antara Facial Process ?” CHEMSOLVE.NET, 3 Apr. 2019.
2. “Antarafacial and Suprafacial.” Wikipedia, Wikimedia Foundation, 15 Aug. 2020.