Question

Increasing order of stability among the three main conformations (i.e., eclipse, anti, gauche) of 2-fluoroethanol is:

• A. $\text{Eclipse < Anti < Gauche}$
• B. $\text{Anti < Gauche < Eclipse}$
• C. $\text{Eclipse < Gauche < Anti}$
• D. $\text{Gauche < Eclipse < Anti}$

Answer 1

The correct option is A $\text{Eclipse < Anti < Gauche}$


Due to hydrogen bonding between $H$ and $F$ gauche conformation is most stable. Eclipsed conformation will be the least stable as it has maximum repulsive interaction.
Hence the correct order is: $\text{Eclipse < Anti < Gauche}$