Determine the absolute configuration of the molecule shown below:

Question

Quizplus · Accepted Answer

To determine the absolute configuration of a molecule, we need to assign priorities to each of the four groups attached to the stereocenter based on their atomic number. In this case, the highest-priority group is the oxygen atom (1), followed by the carbon with a double bond to oxygen (2), then the carbon with a methyl group (3), and finally the carbon with a hydrogen atom (4).

Next, we need to visualize the molecule in three dimensions and determine the direction of the lowest priority group (4). In this case, it is pointing into the plane of the page.

To assign the configuration, we then trace a path from the highest to second-highest priority group in a counterclockwise direction (S) or clockwise direction (R). In this case, starting at the oxygen (1) and going to the carbon with the double bond to oxygen (2) and then to the carbon with the methyl group (3), we can see that the path is in a clockwise direction, so the absolute configuration is R.

Determine the Absolute Configuration of the Molecule Shown Below