Chapter 21, Problem 21.42P

Give the IUPAC name for each compound.

a. d. g.

b. e. h.

c. f.

Interpretation Introduction

(a)

Interpretation: The IUPAC name for the given compound is to be stated.

Concept introduction: One should follow the given steps to give the IUPAC name of a ketone. The first step is finding of longest parent chain that contains a carbonyl carbon. The second step is changing of -e ending of the parent alkane to the suffix -one. The third step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

Answer to Problem 21.42P

The IUPAC name for the given compound is $\text{8-phenyloctan-3-one}$.

Explanation of Solution

The given compound is a ketone.

One should follow the given steps to give the IUPAC name of a ketone. The first step is finding of longest parent chain that contains a carbonyl group. The second step is changing of -e ending of the parent alkane to the suffix -one. The third step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

The given structure shows the presence of eight $\text{C's}$ in the chain. On this chain, the $\text{C}=\text{O}$ group is substituted at $\text{C3}$, and the one phenyl group is substituted at $\text{C8}$.

Figure 1

Thus, the IUPAC name for the given compound is $\text{8-phenyloctan-3-one}$.

Interpretation Introduction

(b)

Interpretation: The IUPAC name for the given compound is to be stated.

Concept introduction: One should follow the given steps to give the IUPAC name of a ketone. The first step is finding of longest parent chain that contains a carbonyl carbon. The second step is changing of -e ending of the parent alkane to the suffix -one. The third step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

Answer to Problem 21.42P

The IUPAC name for the given compound is $\text{2-methylcyclopentanecarbaldehyde}$.

Explanation of Solution

The given compound is an aldehyde.

One should follow the given steps to give the IUPAC name of the aldehyde. The first step is finding of longest parent chain that contains a carbonyl group. The second step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

The given structure shows the presence of five $\text{C's}$ in the cyclic ring. On this ring, the $\text{CHO}$ group is substituted at $\text{C1}$, and one methyl group is substituted at $\text{C2}$.

Figure 2

Thus, the IUPAC name for the given compound is $\text{2-methylcyclopentanecarbaldehyde}$.

Interpretation Introduction

(c)

Interpretation: The IUPAC name for the given compound is to be stated.

Concept introduction: One should follow the given steps to give the IUPAC name of a ketone. The first step is finding of longest parent chain that contains a carbonyl carbon. The second step is changing of -e ending of the parent alkane to the suffix -one. The third step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

Answer to Problem 21.42P

The IUPAC name for the given compound is $\text{5-ethyl-2-methylcyclohexanone}$.

Explanation of Solution

The given compound is a ketone.

One should follow the given steps to give the IUPAC name of a ketone. The first step is finding of longest parent chain that contains a carbonyl group. The second step is changing of -e ending of the parent alkane to the suffix -one. The third step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

The given structure shows the presence of six $\text{C's}$ in the cyclic ring. On this ring, the $\text{C}=\text{O}$ group is substituted at $\text{C1}$, the one methyl group is substituted at $\text{C2}$, and the one ethyl group is substituted at $\text{C5}$.

Figure 3

Thus, the IUPAC name for the given compound is $\text{5-ethyl-2-methylcyclohexanone}$.

Interpretation Introduction

(d)

Interpretation: The IUPAC name for the given compound is to be stated.

Concept introduction: One should follow the given steps to give the IUPAC name of an aldehyde. The first step is finding of longest parent chain that contains an aldehyde group. The second step is changing of -e ending of the parent alkane to the suffix -al. However, when an aldehyde $\left(\text{CHO}\right)$ group is bonded to a ring then after naming of ring, the suffix -carbaldehyde is used. The third step is numbering of chain or ring by putting the $\text{CHO}$ group at $\text{C1}$, and using the general rules of nomenclature.

Answer to Problem 21.42P

The IUPAC name for the given compound is $trans\text{-2-benzylcyclohexancarbaldehyde}$.

Explanation of Solution

The given compound is an aldehyde.

One should follow the given steps to give the IUPAC name of an aldehyde. The first step is finding of longest parent chain that contains an aldehyde group. The second step is changing of -e ending of the parent alkane to the suffix -al. However, when an aldehyde $\left(\text{CHO}\right)$ group is bonded to a ring then after naming of ring, the suffix -carbaldehyde is used. The third step is numbering of chain or ring by putting the $\text{CHO}$ group at $\text{C1}$, and using the general rules of nomenclature.

The given structure shows the presence of six $\text{C's}$ in the cyclic ring. On this ring, an aldehyde group is substituted at $\text{C1}$ (above the plane), and the one benzyl group is substituted at $\text{C2}$.

Figure 4

Thus, the IUPAC name for the given compound is $trans\text{-2-benzylcyclohexancarbaldehyde}$.

Interpretation Introduction

(e)

Interpretation: The IUPAC name for the given compound is to be stated.

Concept introduction: One should follow the given steps to give the IUPAC name of a ketone. The first step is finding of longest parent chain that contains a carbonyl carbon. The second step is changing of -e ending of the parent alkane to the suffix -one. The third step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

Answer to Problem 21.42P

The IUPAC name for the given compound is $\text{1-}\left(\text{2-nitrocyclohexyl}\right)\text{ethanone}$.

Explanation of Solution

The given compound is a ketone.

One should follow the given steps to give the IUPAC name of a ketone. The first step is finding of longest parent chain that contains a carbonyl group. The second step is changing of -e ending of the parent alkane to the suffix -one. The third step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

The given structure shows the presence of six $\text{C's}$ in the cyclic ring. On this ring, the $\text{C}=\text{O}$ group is substituted at $\text{C1}$, and the one nitro group is substituted at $\text{C2}$.

Figure 5

Thus, the IUPAC name for the given compound is $\text{1-}\left(\text{2-nitrocyclohexyl}\right)\text{ethanone}$.

Interpretation Introduction

(f)

Interpretation: The IUPAC name for the given compound is to be stated.

Concept introduction: One should follow the given steps to give the IUPAC name of an aldehyde. The first step is finding of longest parent chain that contains an aldehyde group. The second step is changing of -e ending of the parent alkane to the suffix -al. However, when an aldehyde $\left(\text{CHO}\right)$ group is bonded to a ring then after naming of ring, the suffix -carbaldehyde is used. The third step is numbering of chain or ring by putting the $\text{CHO}$ group at $\text{C1}$, and using the general rules of nomenclature.

Answer to Problem 21.42P

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

Explanation of Solution

The given compound is an aldehyde.

One should follow the given steps to give the IUPAC name of an aldehyde. The first step is finding of longest parent chain that contains an aldehyde group. The second step is changing of -e ending of the parent alkane to the suffix -al. However, when an aldehyde $\left(\text{CHO}\right)$ group is bonded to a ring then after naming of ring, the suffix -carbaldehyde is used. The third step is numbering of chain or ring by putting the $\text{CHO}$ group at $\text{C1}$, and using the general rules of nomenclature.

The given structure shows the presence of six $\text{C's}$ in the longest chain. On this chain, an aldehyde group is substituted at $\text{C1}$, and both $\text{C3}$, and $\text{C4}$ atoms are substituted with one ethyl group.

Figure 6

Thus, the IUPAC name for the given compound is $\text{3, 4-diethylhexanal}$.

(g)

Interpretation Introduction

Interpretation: The IUPAC name for the given compound is to be stated.

Concept introduction: One should follow the given steps to give the IUPAC name of a ketone. The first step is finding of longest parent chain that contains a carbonyl carbon. The second step is changing of -e ending of the parent alkane to the suffix -one. The third step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

Answer to Problem 21.42P

The IUPAC name for the given compound is $\left(E\right)\text{-2, 5-dimethyloct-5-en-4-one}$.

Explanation of Solution

The given compound is a ketone.

One should follow the given steps to give the IUPAC name of a ketone. The first step is finding of longest parent chain that contains a carbonyl group. The second step is changing of -e ending of the parent alkane to the suffix -one. The third step is numbering of chain to give the least number to carbonyl carbon, and using the general rules of nomenclature.

The given structure shows the presence of eight $\text{C's}$ in the longest chain. On this chain, the $\text{C}=\text{O}$ group is substituted at $\text{C4}$, the one methyl group is substituted, both at $\text{C2}$ and $\text{C5}$, and the $\text{C}=\text{C}$ bond is present between $\text{C5}$ and $\text{C6}$. Since the high priority groups are present opposite to each around the $\text{C}=\text{C}$ bond, the prefix used for the nomenclature is $E$.

Figure 7

Thus, the IUPAC name for the given compound is $\left(E\right)\text{-2, 5-dimethyloct-5-en-4-one}$.

Interpretation Introduction

(h)

Interpretation: The IUPAC name for the given compound is to be stated.

Concept introduction: One should follow the given steps to give the IUPAC name of an aldehyde. The first step is finding of longest parent chain that contains an aldehyde group. The second step is changing of -e ending of the parent alkane to the suffix -al. However, when an aldehyde $\left(\text{CHO}\right)$ group is bonded to a ring then after naming of ring, the suffix -carbaldehyde is used. The third step is numbering of chain or ring by putting the $\text{CHO}$ group at $\text{C1}$, and using the general rules of nomenclature.

Answer to Problem 21.42P

The IUPAC name for the given compound is $\text{3, 4-diethyl-2-methylhex-3-enal}$.

Explanation of Solution

The given compound is an aldehyde.

One should follow the given steps to give the IUPAC name of an aldehyde. The first step is finding of longest parent chain that contains an aldehyde group. The second step is changing of -e ending of the parent alkane to the suffix -al. However, when an aldehyde $\left(\text{CHO}\right)$ group is bonded to a ring then after naming of ring, the suffix -carbaldehyde is used. The third step is numbering of chain or ring by putting the $\text{CHO}$ group at $\text{C1}$, and using the general rules of nomenclature.

The given structure shows the presence of six $\text{C's}$ in the longest chain. On this chain, an aldehyde group is substituted at $\text{C1}$, the one methyl group is substituted at $\text{C2}$, the $\text{C}=\text{C}$ bond is present between $\text{C3}$ and $\text{C4}$, and both atoms are substituted with one ethyl group.

Figure 8

Thus, the IUPAC name for the given compound is $\text{3, 4-diethyl-2-methylhex-3-enal}$.

Conclusion

(a) The IUPAC name for the given compound is $\text{8-phenyloctan-3-one}$.

(b) The IUPAC name for the given compound is $\text{2-methylcyclopentanecarbaldehyde}$.

(c) The IUPAC name for the given compound is $\text{5-ethyl-2-methylcyclohexanone}$.

(d) The IUPAC name for the given compound is $trans\text{-2-benzylcyclohexancarbaldehyde}$.

(e) The IUPAC name for the given compound is $\text{1-}\left(\text{2-nitrocyclohexyl}\right)\text{ethanone}$.

(f) The IUPAC name for the given compound is $\text{3, 4-diethylhexanal}$.

(g) The IUPAC name for the given compound is $\left(E\right)\text{-2, 5-dimethyloct-5-en-4-one}$.

(h) The IUPAC name for the given compound is $\text{3, 4-diethyl-2-methylhex-3-enal}$.