A correct name for the following Fischer projection formula is:
R)-3-Pentyn-2-ol
S)-3-Pentyn-2-ol
R)-2-Pentyn-4-ol
S)-2-Pentyn-4-ol
S)-2-Hydroxy-3-pentyne

Question

A correct name for the following Fischer projection formula is: 
R)-3-Pentyn-2-ol 
S)-3-Pentyn-2-ol 
R)-2-Pentyn-4-ol 
S)-2-Pentyn-4-ol 
S)-2-Hydroxy-3-pentyne

Quizplus · Accepted Answer

The molecule has a chiral center at the second carbon from the left, and the hydroxyl group is oriented to project towards the back (away from the viewer). Using the Cahn-Ingold-Prelog priority rules, the priority of the groups attached to this carbon are (highest to lowest): 1) triple bond, 2) carbon atom, 3) hydrogen atom, and 4) hydroxyl group. Drawing a curve from the highest priority group to the second priority group (counterclockwise) gives an S configuration. Therefore, the correct name is (S)-3-Pentyn-2-ol.

A Correct Name for the Following Fischer Projection Formula Is