The Cahn-Ingold-Prelog stereochemical designations used for the following substance are:

Question

Quizplus · Accepted Answer

The molecule has two chiral centers, carbon 2 and 4. The priority of the substituents at carbon 2 are: COOH > CH2OH > H > CH3. The priority of the substituents at carbon 4 are: COOH > CH2OH > OH > CH3. By assigning a priority to each substituent, we find that substituent 1 at carbon 2 is COOH, and substituent 1 at carbon 4 is also COOH. Because both are the same, we need to compare the two substituents at each carbon atom. At carbon 2, the second substituent is CH2OH, and at carbon 4, the second substituent is OH. The higher priority substituents are on opposite sides, so the molecule is 2R,4R.

The Cahn-Ingold-Prelog Stereochemical Designations Used for the Following Substance Are