Chapter 4, Problem 4.50P

Interpretation Introduction

(a)

Interpretation:

It is to be identified whether the two structures in a given pair are constitutional isomers.

Concept introduction:

Constitutional isomers are also knows as structural isomers having the same molecular formula but differing in their connectivity. In order to identify if the two given structures are constitutional isomers, some steps needs to be followed. Start by identifying the longest continuous chain or largest ring of carbons that contains the functional group. Number the carbon atoms involved in the root including the functional group such that the carbon atoms in the functional group receive the lowest possible locator numbers. Also, the substituents attached to the root get the lower possible locator numbers. If two given structures differ in the size of the longest continuous chain, ring or the numbers assigned to the carbon atoms involved in the multiple bonds, the numbers assigned to the carbon atoms to which any substituent is attached, or the identities of the substituents attached to the same-numbered carbon atoms, then the two structures must be constitutional isomers of each other. Otherwise, the molecules have the same connectivity and are not constitutional isomers.

Answer to Problem 4.50P

The two structures in a given pair are not constitutional isomers as they have the same connectivity of atoms.

Explanation of Solution

The two structures in the given pair are

Both the above structures contain the largest carbon ring consisting of six carbon atoms. The ring contains one double bond. Both the structures have the same molecular formula.

Both the structures do not have any substituent attached to the root. For cyclic structures containing $\text{C=C}$ groups, the carbon atoms bearing $\text{C=C}$ are always numbered as C1 and C2. The numbering of the ring is shown below:

The two structures do not differ in their connectivity and, hence, are not constitutional isomers.

Conclusion

Constitutional isomers have the same molecular formula but differ in their connectivity.

Interpretation Introduction

(b)

Interpretation:

It is to be identified whether the two structures in a given pair are constitutional isomers.

Concept introduction:

Constitutional isomers are also knows as structural isomers having the same molecular formula but differing in their connectivity. In order to identify if the two given structures are constitutional isomers, some steps needs to be followed. Start by identifying the longest continuous chain or largest ring of carbons that contains the functional group. Number the carbon atoms involved in the root including the functional group such that the carbon atoms in the functional group receive the lowest possible locator numbers. Also, the substituents attached to the root get the lower possible locator numbers. If two given structures differ in the size of the longest continuous chain, ring or the numbers assigned to the carbon atoms involved in the multiple bonds, the numbers assigned to the carbon atoms to which any substituent is attached, or the identities of the substituents attached to the same-numbered carbon atoms, then the two structures must be constitutional isomers of each other. Otherwise, the molecules have the same connectivity and are not constitutional isomers.

Answer to Problem 4.50P

The two structures in a given pair are constitutional isomers as they have different connectivity of atoms.

Explanation of Solution

The two structures in the given pair are

Both the above structures contain the largest carbon ring consisting of six carbon atoms. The ring contains one double bond and one methyl substituent. Both the structures have the same molecular formula. For cycloalkenes, the carbon atoms bearing $\text{C=C}$ are always numbered as C1 and C2.

For the structure on the left, the numbering can be done so as to give the lowest possible number for the substituent attached. It can be done as

For the structure on the right, the numbering can be done so as to give the lowest possible number for the substituent attached. It can be done as

Note that the position of the substituent is different in both the structures. Thus, the two must be constitutional isomers of each other.

Conclusion

Constitutional isomers have the same molecular formula but differ in their connectivity.

Interpretation Introduction

(c)

Interpretation:

It is to be identified whether the two structures in a given pair are constitutional isomers.

Concept introduction:

Constitutional isomers are also knows as structural isomers having the same molecular formula but differing in their connectivity. In order to identify if the two given structures are constitutional isomers, some steps needs to be followed. Start by identifying the longest continuous chain or largest ring of carbons that contains the functional group. Number the carbon atoms involved in the root including the functional group such that the carbon atoms in the functional group receive the lowest possible locator numbers. Also, the substituents attached to the root get the lower possible locator numbers. If two given structures differ in the size of the longest continuous chain, ring or the numbers assigned to the carbon atoms involved in the multiple bonds, the numbers assigned to the carbon atoms to which any substituent is attached, or the identities of the substituents attached to the same-numbered carbon atoms, then the two structures must be constitutional isomers of each other. Otherwise, the molecules have the same connectivity and are not constitutional isomers.

Answer to Problem 4.50P

The two structures in a given pair are not constitutional isomers as they have the same connectivity of atoms.

Explanation of Solution

The two structures in the given pair are

The longest continuous chain of carbon atoms in each molecule has six carbons. The molecular formula for both the structures is the same. The carbon atoms are numbered 1 through 6 so that the first methyl group is encountered on C3 carbon atom as shown below:

Because the methyl group is attached to C3 carbon atoms in both the molecules, the molecules have the same connectivity of atoms and therefore are not constitutional isomers.

Conclusion

Constitutional isomers have the same molecular formula but differ in their connectivity.

Interpretation Introduction

(d)

Interpretation:

It is to be identified whether the two structures in a given pair are constitutional isomers.

Concept introduction:

Constitutional isomers are also knows as structural isomers having the same molecular formula but differing in their connectivity. In order to identify if the two given structures are constitutional isomers, some steps needs to be followed. Start by identifying the longest continuous chain or largest ring of carbons that contains the functional group. Number the carbon atoms involved in the root including the functional group such that the carbon atoms in the functional group receive the lowest possible locator numbers. Also, the substituents attached to the root get the lower possible locator numbers. If two given structures differ in the size of the longest continuous chain, ring or the numbers assigned to the carbon atoms involved in the multiple bonds, the numbers assigned to the carbon atoms to which any substituent is attached, or the identities of the substituents attached to the same-numbered carbon atoms, then the two structures must be constitutional isomers of each other. Otherwise, the molecules have the same connectivity and are not constitutional isomers.

Answer to Problem 4.50P

The two structures in a given pair are not constitutional isomers as they have the same connectivity of atoms.

Explanation of Solution

The two structures in the given pair are

The longest continuous chain of carbon atoms in each molecule has six carbons. The molecular formula for both the structures is the same. The carbon atoms are numbered 1 through 6 so that the carbon atoms to which $\text{-OH}$ is attached gets the lowest possible locator number. The ethyl group is encountered on C3 carbon atom of the root in both the structures, as shown below:

Because the ethyl group is attached to C3 carbon atoms in both the molecules, the molecules have the same connectivity of atoms and therefore are not constitutional isomers.

Conclusion

Constitutional isomers have the same molecular formula but differ in their connectivity.

Interpretation Introduction

(e)

Interpretation:

It is to be identified whether the two structures in a given pair are constitutional isomers.

Concept introduction:

Constitutional isomers are also knows as structural isomers having the same molecular formula but differing in their connectivity. In order to identify if the two given structures are constitutional isomers, some steps needs to be followed. Start by identifying the longest continuous chain or largest ring of carbons that contains the functional group. Number the carbon atoms involved in the root including the functional group such that the carbon atoms in the functional group receive the lowest possible locator numbers. Also, the substituents attached to the root get the lower possible locator numbers. If two given structures differ in the size of the longest continuous chain, ring or the numbers assigned to the carbon atoms involved in the multiple bonds, the numbers assigned to the carbon atoms to which any substituent is attached, or the identities of the substituents attached to the same-numbered carbon atoms, then the two structures must be constitutional isomers of each other. Otherwise, the molecules have the same connectivity and are not constitutional isomers.

Answer to Problem 4.50P

The two structures in a given pair are constitutional isomers as they have different connectivity of atoms.

Explanation of Solution

The two structures in the given pair are

Both the above structures contain the largest carbon ring consisting of six carbon atoms. The ring contains double bonds. Both the structures have the same molecular formula.

Both the structures do not have any substituent attached to the root. For cyclic structures containing $\text{C=C}$ groups, the carbon atoms bearing $\text{C=C}$ are always numbered as C1 and C2. The numbering of the ring is shown below:

Note that there are three double bonds for the ring on the left and two for the ring on the right. The two structures differ in their connectivity and, hence, are constitutional isomers.

Conclusion

Constitutional isomers have the same molecular formula but differ in their connectivity.

Interpretation Introduction

(g)

Interpretation:

It is to be identified whether the two structures in a given pair are constitutional isomers.

Concept introduction:

Constitutional isomers are also knows as structural isomers having the same molecular formula but differing in their connectivity. In order to identify if the two given structures are constitutional isomers, some steps needs to be followed. Start by identifying the longest continuous chain or largest ring of carbons that contains the functional group. Number the carbon atoms involved in the root including the functional group such that the carbon atoms in the functional group receive the lowest possible locator numbers. Also, the substituents attached to the root get the lower possible locator numbers. If two given structures differ in the size of the longest continuous chain, ring or the numbers assigned to the carbon atoms involved in the multiple bonds, the numbers assigned to the carbon atoms to which any substituent is attached, or the identities of the substituents attached to the same-numbered carbon atoms, then the two structures must be constitutional isomers of each other. Otherwise, the molecules have the same connectivity and are not constitutional isomers.

Answer to Problem 4.50P

The two structures in a given pair are not constitutional isomers as they have different molecular formula.

Explanation of Solution

The two structures in the given pair are

Out of the two gives compounds, one is a ring of six carbon atoms, while the other is a straight chain of six carbon atoms. Though both the structures have the root with six carbon atoms, the number of hydrogen atoms is different for both the structures. Thus, these two structures have different molecular formulas. Since these two structures have different molecular formulas, they cannot be isomers in the first place. Hence, they are definitely not constitutional isomers.

Conclusion

Constitutional isomers have the same molecular formula but differ in their connectivity.

Interpretation Introduction

(h)

Interpretation:

It is to be identified whether the two structures in a given pair are constitutional isomers.

Concept introduction:

Constitutional isomers are also knows as structural isomers having the same molecular formula but differing in their connectivity. In order to identify if the two given structures are constitutional isomers, some steps needs to be followed. Start by identifying the longest continuous chain or largest ring of carbons that contains the functional group. Number the carbon atoms involved in the root including the functional group such that the carbon atoms in the functional group receive the lowest possible locator numbers. Also, the substituents attached to the root get the lower possible locator numbers. If two given structures differ in the size of the longest continuous chain, ring or the numbers assigned to the carbon atoms involved in the multiple bonds, the numbers assigned to the carbon atoms to which any substituent is attached, or the identities of the substituents attached to the same-numbered carbon atoms, then the two structures must be constitutional isomers of each other. Otherwise, the molecules have the same connectivity and are not constitutional isomers.

Answer to Problem 4.50P

The two structures in a given pair are constitutional isomers as they have different connectivity of atoms.

Explanation of Solution

The two structures in the given pair are

Both the above structures contain the largest carbon ring consisting of five carbon atoms. Both the structures have the same molecular formula.

The ring on the left can be numbered in such a way so that the double bonded carbon atom gets the lowest possible locator number.

The ring on the right can be numbered in such a way that each of the double bonded carbon atom gets C1 and C2 numbers. The numbering for both the structures is shown below:

The ring on the left has $\text{C=O}$ group while the ring on the right has $\text{C=C and -OH}$ group.

Note that the connectivity of the two structures is different.

Thus, the two must be constitutional isomers of each other.

Conclusion

Constitutional isomers have the same molecular formula but differ in their connectivity.