Determine the absolute configuration of the molecule shown below:

Question

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Using Cahn-Ingold-Prelog priority rules, we assign priorities to each of the groups attached to the stereocenter. The groups attached to the carbon atom are chlorine (1), bromine (2), methyl group (3), and hydrogen (4). In order to determine the absolute configuration, we arrange the groups in decreasing order of priority (highest to lowest). When the lowest priority group (hydrogen) is pointed away, we observe the orientation of the remaining three groups. If they are arranged in a clockwise direction, the configuration is R. If they are arranged in a counterclockwise direction, the configuration is S. In this case, the chlorine and bromine groups are on the same side, and the methyl group and hydrogen are on opposite sides, which is counterclockwise (S configuration). However, we want to know the absolute configuration, which refers to the spatial arrangement of atoms in a molecule by considering the actual handedness of the molecule (right or left). This can only be determined experimentally, such as using X-ray crystallography or NMR spectroscopy. Therefore, we can only assign the stereochemistry as R or S based on the Cahn-Ingold-Prelog priority rules.

Determine the Absolute Configuration of the Molecule Shown Below