Chapter B, Problem B.32P

Interpretation Introduction

(a)

Interpretation:

The IUPAC name for the given compound is to be determined.

Concept introduction:

For a molecule that has more than one double bond or triple bond, the IUPAC name must indicate the number of double bonds or triple bonds present as well as their locations. To name the molecule with multiple double/triple bonds, establish the root as the longest carbon chain or the largest carbon ring that contains the greatest number of entire $\text{C=C or C}\equiv \text{C}$ groups. Number the chain or ring so that each successive $\text{C=C or C}\equiv \text{C}$ group is encountered the earliest. For each pair of $\text{C=C or C}\equiv \text{C}$ atoms, identify the lower of the two locator numbers. Immediately before the ene or yne suffix, add the letter ‘a’ followed by the above set of locator numbers, and then add the prefix di, tri, etc. to specify the number of double or triple bonds. The substituents attached to the root are named in an alphabetical order.

Answer to Problem B.32P

The IUPAC name for the given compound is $\text{2, 4-dichlorohexa-1, 3-diene}$

Explanation of Solution

The given molecule is

In the given molecule, the longest carbon chain containing all $\text{C}=\text{C}$ groups has six carbon atoms. As there are two $\text{C}=\text{C}$ groups, the letter ‘a’ is added before the suffix, so the root name is hexa-diene. Numbering begins at the right terminal carbon atom because that gives the first $\text{C}=\text{C}$ group the lowest locator number - 1. So, the set of locator numbers assigned to all $\text{C}=\text{C}$ groups is 1, 3. Hence, the root name for this molecule is $\text{hexa-1, 3-diene}$. The numbering is shown as:

At carbon atoms C2 and C4 of the root, two chlorine atoms are present. Thus, the complete IUPAC name of this molecule is $\text{2, 4-dichlorohexa-1, 3-diene}$.

Conclusion

The IUPAC name of the compound is written according to the rules for nomenclature.

Interpretation Introduction

(b)

Interpretation:

The IUPAC name for the given compound is to be determined.

Concept introduction:

For a molecule that has more than one double bond or triple bond, the IUPAC name must indicate the number of double bonds or triple bonds present as well as their locations. To name the molecule with multiple double/triple bonds, establish the root as the longest carbon chain or the largest carbon ring that contains the greatest number of entire $\text{C=C or C}\equiv \text{C}$ groups. Number the chain or ring so that each successive $\text{C=C or C}\equiv \text{C}$ group is encountered the earliest. For each pair of $\text{C=C or C}\equiv \text{C}$ atoms, identify the lower of the two locator numbers. Immediately before the ene or yne suffix, add the letter ‘a’ followed by the above set of locator numbers, and then add the prefix di, tri, etc. to specify the number of double or triple bonds. The substituents attached to the root are named in an alphabetical order.

Answer to Problem B.32P

The IUPAC name for the given compound is $\text{4, 5, 5-tribromocyclohexa-1, 3-diene}$

Explanation of Solution

The given compound is

In the given molecule, the largest carbon ring containing all two $\text{C=C}$ groups has six carbon atoms. Because of multiple $\text{C=C}$ groups, the letter ‘a’ is added before the suffix, so the root name is cyclohexa-diene. Numbering begins at the double bonded carbon atom that gives the first $\text{C=C}$ group the lowest locator number, 1. So, the set of locator numbers assigned to all $\text{C=C}$ groups is 1, 3. So, the complete root name is $\text{cyclohexa-1, 3-diene}$. The numbering is shown as

Three bromine atoms are present as substituents at carbon atoms C4, C5, and C5 to the root. The prefix ‘tri’ must be used to indicate the number of substituents present to the root. Thus, the complete IUPAC name of this molecule is $\text{4, 5, 5-tribromocyclohexa-1, 3-diene}$.

Conclusion

The IUPAC name of the compound is written according to the rules for nomenclature.

Interpretation Introduction

(c)

Interpretation:

The IUPAC name for the given compound is to be determined.

Concept introduction:

For a molecule that has more than one double bond or triple bond, the IUPAC name must indicate the number of double bonds or triple bonds present as well as their locations. To name the molecule with multiple double/triple bonds, establish the root as the longest carbon chain or the largest carbon ring that contains the greatest number of entire $\text{C=C or C}\equiv \text{C}$ groups. Number the chain or ring so that each successive $\text{C=C or C}\equiv \text{C}$ group is encountered the earliest. For each pair of $\text{C=C or C}\equiv \text{C}$ atoms, identify the lower of the two locator numbers. Immediately before the ene or yne suffix, add the letter ‘a’ followed by the above set of locator numbers, and then add the prefix di, tri, etc. to specify the number of double or triple bonds. The substituents attached to the root are named in an alphabetical order.

Answer to Problem B.32P

The IUPAC name for the given compound is $\text{3-methoxyhexa-1, 4-diyne}$.

Explanation of Solution

The given molecule is

In the given molecule, the longest carbon chain containing all two $\text{C}\equiv \text{C}$ groups has six carbon atoms. Because of two $\text{C}\equiv \text{C}$ groups, the letter ‘a’ is added before the suffix, so the root name is hexa-diyne. Numbering begins the top-right carbon atom containing the triple bond because that gives the first $\text{C}\equiv \text{C}$ group the lowest locator number, 1. So, the set of locator numbers assigned to all three $\text{C}\equiv \text{C}$ groups is 1, 4. So, the complete root name is $\text{hexa-1, 4-diyne}$. The numbering is shown as:

One methoxy substituent is attached to the C3 carbon atom of the root. Thus, the complete IUPAC name of this molecule is $\text{3-methoxyhexa-1, 4-diyne}$.

Conclusion

The IUPAC name of the compound is written according to the rules for nomenclature.

Interpretation Introduction

(d)

Interpretation:

The IUPAC name for the given compound is to be determined.

Concept introduction:

For a molecule that has more than one double bond or triple bond, the IUPAC name must indicate the number of double bonds or triple bonds present as well as their locations. To name the molecule with multiple double/triple bonds, establish the root as the longest carbon chain or the largest carbon ring that contains the greatest number of entire $\text{C=C or C}\equiv \text{C}$ groups. Number the chain or ring so that each successive $\text{C=C or C}\equiv \text{C}$ group is encountered the earliest. For each pair of $\text{C=C or C}\equiv \text{C}$ atoms, identify the lower of the two locator numbers. Immediately before the ene or yne suffix, add the letter ‘a’ followed by the above set of locator numbers, and then add the prefix di, tri, etc. to specify the number of double or triple bonds. The substituents attached to the root are named in an alphabetical order.

Answer to Problem B.32P

The IUPAC name for the given compound is $\text{1-chloropenta-1, 3-diyne}$.

Explanation of Solution

The given molecule is

In the given molecule, the longest carbon chain containing all $\text{C}\equiv \text{C}$ groups has five carbon atoms. Because of two $\text{C}\equiv \text{C}$ groups, the letter ‘a’ is added before the suffix, so the root name is penta-diyne. Numbering begins at the left terminal triple bonded carbon atom because that gives the first $\text{C}\equiv \text{C}$ group the lowest locator number, 1. So, the set of locator numbers assigned to all $\text{C}\equiv \text{C}$ groups is 1, 3. Hence, the root name for this molecule is $\text{penta-1, 3-diyne}$. The numbering is shown as:

At carbon atom C1of the root, one chlorine atom is present.

Thus, the complete IUPAC name of this molecule is $\text{1-chloropenta-1, 3-diyne}$.

Conclusion

The IUPAC name of the compound is written according to the rules for nomenclature.

Interpretation Introduction

(e)

Interpretation:

The IUPAC name for the given compound is to be determined.

Concept introduction:

For a molecule that has more than one double bond or triple bond, the IUPAC name must indicate the number of double bonds or triple bonds present as well as their locations. To name the molecule with multiple double/triple bonds, establish the root as the longest carbon chain or the largest carbon ring that contains the greatest number of entire $\text{C=C or C}\equiv \text{C}$ groups. Number the chain or ring so that each successive $\text{C=C or C}\equiv \text{C}$ group is encountered the earliest. For each pair of $\text{C=C or C}\equiv \text{C}$ atoms, identify the lower of the two locator numbers. Immediately before the ene or yne suffix, add the letter ‘a’ followed by the above set of locator numbers, and then add the prefix di, tri, etc. to specify the number of double or triple bonds. The substituents attached to the root are named in the alphabetical order.

Answer to Problem B.32P

The IUPAC name for the given compound is $\text{1, 2, 3, 4-tetramethylcycloocta-1, 3, 6-triene}$.

Explanation of Solution

The given compound is

In the given molecule, the largest carbon ring containing all three $\text{C=C}$ groups has eight carbon atoms. Because of multiple $\text{C=C}$ groups, the letter ‘a’ is added before the suffix, so the root name is cycloocta-triene. Numbering begins at the double bonded carbon atom containing the methyl group because that gives the first $\text{C=C}$ group the lowest locator number, 1. So, the set of locator numbers assigned to all $\text{C=C}$ groups is 1, 3, 6. So, the complete root name is $\text{cycloocta-1, 3, 6-triene}$. The numbering is shown as:

Four methyl substituents are attached at C1, C2, C3, and C4 carbon atoms of the root. The prefix ‘tetra’ should be used to indicate four methyl substituents.

Thus, the complete IUPAC name of this molecule is $\text{1, 2, 3, 4-tetramethylcycloocta-1, 3, 6-triene}$.

Conclusion

The IUPAC name of the compound is written according to the rules for nomenclature.

Interpretation Introduction

(f)

Interpretation:

The IUPAC name for the given compound is to be determined.

Concept introduction:

For a molecule that has more than one double bond or triple bond, the IUPAC name must indicate the number of double bonds or triple bonds present as well as their locations. To name the molecule with multiple double/triple bonds, establish the root as the longest carbon chain or the largest carbon ring that contains the greatest number of entire $\text{C=C or C}\equiv \text{C}$ groups. Number the chain or ring so that each successive $\text{C=C or C}\equiv \text{C}$ group is encountered the earliest. For each pair of $\text{C=C or C}\equiv \text{C}$ atoms, identify the lower of the two locator numbers. Immediately before the ene or yne suffix, add the letter ‘a’ followed by the above set of locator numbers, and then add the prefix di, tri, etc. to specify the number of double or triple bonds. The substituents attached to the root are named in an alphabetical order.

Answer to Problem B.32P

The IUPAC name for the given compound is $\text{2-cyclopropylhepta-1, 4, 6-triene}$

Explanation of Solution

The given molecule is

In the given molecule, the longest carbon chain containing all $\text{C}=\text{C}$ groups has seven carbon atoms. Because of three $\text{C}=\text{C}$ groups, the letter ‘a’ is added before the suffix, so the root name is hepta-triene. Numbering begins at the left terminal carbon atom because that gives the first $\text{C}=\text{C}$ group the lowest locator number, 1, as well as the substituent the lowest locator number. So, the set of locator numbers assigned to all $\text{C}=\text{C}$ groups is 1, 4, 6. Hence, the root name for this molecule is $\text{hepta-1, 4, 6-triene}$. The numbering is shown as:

At carbon atom C2 of the root, one cyclopropyl group is attached.

Thus, the complete IUPAC name of this molecule is $\text{2-cyclopropylhepta-1, 4, 6-triene}$.

Conclusion

The IUPAC name of the compound is written according to the rules for nomenclature.

Interpretation Introduction

(g)

Interpretation:

The IUPAC name for the given compound is to be determined.

Concept introduction:

For a molecule that has more than one double bond or triple bond, the IUPAC name must indicate the number of double bonds or triple bonds present as well as their locations. To name the molecule with multiple double/triple bonds, establish the root as the longest carbon chain or the largest carbon ring that contains the greatest number of entire $\text{C=C or C}\equiv \text{C}$ groups. Number the chain or ring so that each successive $\text{C=C or C}\equiv \text{C}$ group is encountered the earliest. For each pair of $\text{C=C or C}\equiv \text{C}$ atoms, identify the lower of the two locator numbers. Immediately before the ene or yne suffix, add the letter ‘a’ followed by the above set of locator numbers, and then add the prefix di, tri, etc. to specify the number of double or triple bonds. The substituents attached to the root are named in the alphabetical order.

Answer to Problem B.32P

The IUPAC name for the given compound is

Explanation of Solution

The given molecule is

In the given molecule, the longest carbon chain containing all $\text{C}=\text{C}$ groups has eight carbon atoms. Because of two $\text{C}=\text{C}$ groups, the letter ‘a’ is added before the suffix, so the root name is hexa-diene. Numbering can be done from either ends, as all the bonds are equidistant. So, the set of locator numbers assigned to all $\text{C}=\text{C}$ groups is 1, 3, 5, 7. Hence, the root name for this molecule is $\text{hepta-1, 3, 5, 7-tetraene}$. The numbering is shown as:

There are no substituents attached to the root. Thus, the complete IUPAC name of this molecule is $\text{hepta-1, 3, 5, 7-tetraene}$.

Conclusion

The IUPAC name of the compound is written according to the rules for nomenclature.