Question

The most stable conformation of $3-fluorobutan-2-ol$ is:

• A. Fully eclipsed form
• B. Partially eclipsed form
• C. Gauche form
• D. Anti form

Answer 1

Answer: (C)

Gauche form

Partially eclipsed and fully eclipsed forms are highly unstable due to steric hindrance caused by the bulky groups present very close to each other.

Anti-form is stable because bulky groups are present far away and opposite from each other.

Gauche form is highly stable due to the presence of intra-molecular hydrogen bonding between OH and F groups.

Order of stability: $\text{fully eclipsed}<\text{partially eclipsed}<\text{anti-form}<\text{gauche form}$