6.40E

Question

Answer questions 6-39 taking all stereoisomers into account.

(a)

 


 

(b)

 

 

 

 

(c)

Step-by-Step Solution

Verified
Answer

(a)


 

        (S)-2-chlorobutane

 

 

         (R)-2-chlorobutane

 


              
1-chlorobutane

 

(b)

 (R)-1-chloro-2-methylbutane

(S)-1-chloro-2-methylbutane

2-chloro-2-methylbutane

(R)-2-chloro-3-methylbutane

(S)-2-chloro-3-methylbutane

   1-chloro-3methylbutane

 

(c)

    (chloromethyl)cyclopentane

 1-chloro-1-methylcyclopentane

 

(1R)-1-chloro-2-methylcyclopentane

(1S)-1-chlro-2-methylcyclopentane

(1R)-1-chloro-3-methylccylopentane

   (1S)-1-chloro-3-methylcyclopentane

1Step 1: n-Butane

In n-butane, there are two types of hydrogen. One type is attached with terminal carbon and the second type is attached with non-terminal carbon. Therefore, without considering the stereochemistry for radical chlorination only two monochlorinated products are possible which are as shown:

          

2Step 2: Isopentane

In isopentane, there are four types of hydrogen. Therefore, without considering the stereochemistry for radical chlorination four monochlorinated products are possible which are as follows:



3Step 3: Given compound

In the given compound there are four types of hydrogen. Therefore, without considering the stereochemistry for radical chlorination four types of monochlorinated products are possible as shown:



4Step 4: a) Stereochemistry

If we consider stereochemistry, compound A is optically active as the marked carbon is chiral. Therefore, two possible isomers are there. Compound B is optically inactive. Thus, considering the stereochemistry for radical chlorination total of three monochlorinated products are possible which are as shown:

   (S)-2-chlorobutane

 

        (R)-2-chlorobutane

 

            1-chlorobutane


5Step 5: b) Stereochemistry

If we consider the stereochemistry, compounds A and C are optically active as the marked carbons are chiral. Therefore, two possible isomers are there for each of A and C. Compounds B and D are optically inactive. Therefore, considering the stereochemistry for radical chlorination total of six monochlorinated products are possible as shown:

(R)-1-chloro-2-methylbutane


(S)-1-chloro-2-methylbutane


2-chloro-2-methylbutane

(R)-2-chloro-3-methylbutane



(S)-2-chloro-3-methylbutane


1-chloro-3methylbutane

6Step 6: c) Stereochemistry






If we consider the stereochemistry, compounds C and D are optically active as the marked carbons are chiral. Therefore, two possible isomers are there for each of C and D. Compounds A and B are optically inactive. Therefore, considering the stereochemistry for radical chlorination total of six monochlorinated products are possible which are as shown:


(chloromethyl)cyclopentane


1-chloro-1-methylcyclopentane


(1R)-1-chloro-2-methylcyclopentane


(1S)-1-chlro-2-methylcyclopentane


(1R)-1-chloro-3-methylccylopentane


(1S)-1-chloro-3-methylcyclopentane