Question

Which among the following functional groups has been given the highest priority while assigning $R-S$ configuration?

• A. $-C_6{H}_5$
• B. $-CN$
• C. $-C_2{H}_5$
• D. $-C{H}_3$

Answer 1

Answer: (B)

$-CN$

$-CN$ has the highest atomic number first we will see the atom that has the highest atomic number that is directly attached to carbon then remaining atoms.

In given options, all are directly attached to carbon with a carbon or hydrogen. But in $-CN$ carbon has Nitrogen with a highest atomic number than Hydrogen.