Question

13 multiple choice 2 points name the haloalkane using r or s description. ch3 ch3 cl (s)- 1-chloro-3,3-dimethylcyclohexane (r)- 1-chloro-3,3-dimethylcyclohexane (s)- 3-chloro-1,1-dimethylcyclohexane (r)- 3-chloro-1,1-dimethylcyclohexane

Explanation:

Step1: Determine the priority of substituents

According to CIP rules, \(Cl\) (atomic number \(17\)) has higher priority than \(C\) (atomic number \(6\)). So \(Cl\) is priority \(1\), and the cyclohexane ring (with attached groups) is considered. The two methyl groups on carbon \(3\) are lower priority compared to \(Cl\).

Step2: Visualize the orientation

Assume the lowest - priority group (in this case, part of the cyclohexane ring away from the chiral center in a way that we can apply the \(R/S\) rule). The \(Cl\) (priority \(1\)), the carbon chain (priority \(2\)), and the other part (priority \(3\)) are oriented. When we look at the chiral center (carbon \(1\) with \(Cl\) attached), the rotation from \(1\) (\(Cl\)) to \(2\) (carbon chain) to \(3\) (other part) is counter - clockwise.

Step3: Assign \(R/S\)

Since the rotation is counter - clockwise, it is \(S\). And the correct naming has the chlorine on carbon \(1\) (as per numbering rules for haloalkanes in cycloalkanes, halogen gets priority in numbering over alkyl groups in some cases, here the structure has the \(Cl\) on carbon \(1\) and two methyls on carbon \(3\)). So it is \((S)-1 -\text{chloro}-3,3 -\text{dimethylcyclohexane}\)

Answer:

(S)- 1 - chloro - 3,3 - dimethylcyclohexane