Figure 4.5 a) The staggered conformation of ethane. b) The Newman projection
formula for the staggered conformation.
- Staggered conformation: allows the maximum separation of the electron pairs
of the six C—H bonds ⇒ has the lowest energy ⇒ most stable conformation. - Newman projection formula:
- Sawhorse formula:
Newman projection formula Sawhorse formula
The hydrogen atoms have been omitted for clarity.- Eclipsed conformation: maximum repulsive interaction between the electron
pairs of the six C—H bonds ⇒ has the highest energy^ ⇒^ least stable^
conformation.
Figure 4.6 The eclipsed conformation of ethane. b) The Newman projection
formula for the eclipsed conformation.
- Torsional barrier: the energy barrier to rotation of a single bond.
- In ethane the difference in energy between the staggered and eclipsed