Question

The Cahn-Ingold-Prelog $(CIP)$ priorities of the group and the absolute configuration (R/S) of the following compound are

• A. $-CH_{2}OH >\, -CH(CH_{3})_{2} >\, -CH = CH_{2} >\, -CH_{3}$ and $S$
• B. $-CH_{2}OH >\, -CH = CH_{2} >\, -CH(CH_{3})_{2} >\, -CH_{3}$ and $S$
• C. $-CH_{2}OH >\, -CH = CH_{2} >\, -CH(CH_{3})_{2} >\, -CH_{3}$ and $R$
• D. $-CH_{2}OH >\, -CH(CH_{3})_{2} >\, -CH = CH_{2} >\, -CH_{3}$ and $R$

Answer 1

Answer: (B)

The priority number of a ligand is based on the atomic no. of the element in the ligand that bonds the ligand to chiral center. The higher the atomic number, the higher the proirity