Chapter 9.SE, Problem 27AP

Draw structures corresponding to the following names:

(a) 3, 3-Dimethyl-4-octyne

(b) 3-Ethyl-5-methyl-1, 6, 8-decatriyne

(c) 2, 2, 5, 5-Tetramethyl-3-hexyne

(d) 3, 4-Dimethylcyclodecyne

(e) 3, 5-Heptadien-1-yne

(f) 3-Chloro-4, 4-dimethyl-1-nonen-6-yne

(g) 3-sec-Butyl-1-heptyne

(h) 5-tert-Buty1-2-methyl-3-octyne

Interpretation Introduction

a) 3,3-Dimethyl-4-octyne.

Interpretation:

The structure of 3,3-Dimethyl-4-octyne is to be drawn.

Concept introduction:

The longest carbon chain containing the triple bond to be chosen. Based on the name of the parent compound–the alkyne name ends with the suffix–yne. The chain is to be numbered from the end that gives the lowest number to the carbon in triple bond. Substituents are to be numbered according to their positions in the chain and listed alphabetically. The position of the triple bond is indicated by giving the number of the first alkyne carbon before the name of the parent name. If more than one triple bond is present, their positions are indicated with the suffixes -diyne, -triyne and so on.

To draw:

The structure corresponding to the IUPAC name 3,3-dimethyl-4-octyne.

Answer to Problem 27AP

The structure corresponding to the IUPAC name 3,3-dimethyl-4-octyne is

Explanation of Solution

The name shows that the longest carbon chain should contain eight carbons with a triple bond between C₄ & C₅ and two methyl groups should be present on C₃.

Conclusion

The structure corresponding to the IUPAC name 3,3-dimethyl-4-octyne is

Interpretation Introduction

b) 3-Ethyl-5-methyl-1,6,8-decatriyne.

Interpretation:

The structure of 3-ethyl-5-methyl-1,6,8-decatriyne is to be drawn.

Concept introduction:

The longest carbon chain containing the triple bond to be chosen. Based on the name of the parent compound–the alkyne name ends with the suffix–yne. The chain is to be numbered from the end that gives the lowest number to the carbon in triple bond. Substituents are to be numbered according to their positions in the chain and listed alphabetically. The position of the triple bond is indicated by giving the number of the first alkyne carbon before the name of the parent name. If more than one triple bond is present, their positions are indicated with the suffixes -diyne, -triyne and so on.

To draw:

The structure corresponding to the IUPAC name 3-ethyl-5-methyl-1,6,8-decatriyne.

Answer to Problem 27AP

The structure corresponding to the IUPAC name 3-ethyl-5-methyl-1,6,8-decatriyne is

Explanation of Solution

The name shows that the longest carbon chain should contain ten carbons with three triple bonds, one between C₁ & C₂, another between C₆ & C₇ a third one between C₈ & C₉, an ethyl group on C₃ and a methyl group on C₅.

Conclusion

The structure corresponding to the IUPAC name 3-ethyl-5-methyl-1,6,8-decatriyne is

Interpretation Introduction

c) 2,2,5,5- tetramethyl-3-hexyne.

Interpretation:

The structure of 2,2,5,5- tetramethyl-3-hexyne is to be drawn.

Concept introduction:

The longest carbon chain containing the triple bond to be chosen. Based on the name of the parent compound–the alkyne name ends with the suffix–yne. The chain is to be numbered from the end that gives the lowest number to the carbon in triple bond. Substituents are to be numbered according to their positions in the chain and listed alphabetically. The position of the triple bond is indicated by giving the number of the first alkyne carbon before the name of the parent name. If more than one triple bond is present, their positions are indicated with the suffixes -diyne, -triyne and so on.

To draw:

The structure corresponding to the IUPAC name 2,2,5,5- tetramethyl-3-hexyne.

Answer to Problem 27AP

The structure corresponding to the IUPAC name 2,2,5,5- tetramethyl-3-hexyne is

Explanation of Solution

The name shows that the longest carbon chain should contain six carbons with a triple bond between C₃ & C₄ and four methyl groups, two on C₂ and another two on C₅.

Conclusion

The structure corresponding to the IUPAC name 2,2,5,5- tetramethyl-3-hexyne is

Interpretation Introduction

d) 3,4-Dimethylcyclodeceyne.

Interpretation:

The structure of 3,4-Dimethylcyclodeceyne is to be drawn.

Concept introduction:

The longest carbon chain containing the triple bond to be chosen. Based on the name of the parent compound–the alkyne name ends with the suffix–yne. The chain is to be numbered from the end that gives the lowest number to the carbon in triple bond. Substituents are to be numbered according to their positions in the chain and listed alphabetically. The position of the triple bond is indicated by giving the number of the first alkyne carbon before the name of the parent name. If more than one triple bond is present, their positions are indicated with the suffixes -diyne, -triyne and so on.

To draw:

The structure corresponding to the IUPAC name 3,4-dimethyl cyclodeceyne.

Answer to Problem 27AP

The structure corresponding to the IUPAC name 3,4-dimethyl cyclodeceyne is

Explanation of Solution

The name shows that the compound contains a ring made up of ten carbon atoms with a triple bond attached to two methyl groups on C₃ and C₄.

Conclusion

The structure corresponding to the IUPAC name 3,4-dimethyl cyclodeceyne is

Interpretation Introduction

e) 3,5-Heptadiene-1-yne.

Interpretation:

The structure of 3,5-heptadiene-1-yne is to be drawn.

Concept introduction:

The longest carbon chain which contains the carbon-carbon triple bond is chosen. The chain is numbered from the end that gives the lowest number to the carbon in triple bond. Compounds with more than one triple bond are called diynes, triynes and so forth. Compounds containing both double bond and triple bonds are called as enynes. The chain is numbered from the end nearer to the multiple bonds, double or triple. When there is a choice in numbering the double bond is given preference and the lowest number is assigned to it.

To draw:

The structure corresponding to the IUPAC name 3,5-heptadiene-1-yne.

Answer to Problem 27AP

The structure corresponding to the IUPAC name 3,5-heptadiene-1-yne is

Explanation of Solution

The name shows that the longest carbon chain should contain seven carbons with a triple bond between C₁ & C₂ and two double bonds, one between C₃ & C₄ and another between C₅ & C₆.

Conclusion

The structure corresponding to the IUPAC name 3,5-heptadiene-1-yne is

Interpretation Introduction

f) 3-Chloro-4,4-dimethyl-1-nonene-6-yne.

Interpretation:

The structure of 3-chloro-4,4-dimethyl-1-nonene-6-yne is to be drawn.

Concept introduction:

The longest carbon chain which contains the carbon-carbon triple bond is chosen. The chain is numbered from the end that gives the lowest number to the carbon in triple bond. Compounds with more than one triple bond are called diynes, triynes and so forth. Compounds containing both double bond and triple bonds are called as enynes. The chain is numbered from the end nearer to the multiple bonds, double or triple. When there is a choice in numbering the double bond is given preference and the lowest number is assigned to it.

To draw:

The structure corresponding to the IUPAC name 3-chloro-4,4-dimethyl-1-nonene-6-yne.

Answer to Problem 27AP

The structure corresponding to the IUPAC name 3-chloro-4,4-dimethyl-1-nonene-6-yne is

Explanation of Solution

The name shows that the longest carbon chain should contain nine carbons with a triple bond between C₆ & C₇, one double bond between C₁ & C₂, a chlorine atom on C₃ and two methyl groups on C₄.

Conclusion

The structure corresponding to the IUPAC name 3-chloro-4,4-dimethyl-1-nonene-6-yne is

Interpretation Introduction

g) 3-sec-Butyl-1-heptyne.

Interpretation:

The structure of 3-sec-Butyl-1-heptyne is to be drawn.

Concept introduction:

The longest carbon chain containing the triple bond to be chosen. Based on the name of the parent compound–the alkyne name ends with the suffix–yne. The chain is to be numbered from the end that gives the lowest number to the carbon in triple bond. Substituents are to be numbered according to their positions in the chain and listed alphabetically. The position of the triple bond is indicated by giving the number of the first alkyne carbon before the name of the parent name. If more than one triple bond is present, their positions are indicated with the suffixes -diyne, -triyne and so on.

To draw:

The structure corresponding to the IUPAC name 3-sec-butyl-1-heptyne.

Answer to Problem 27AP

The structure corresponding to the IUPAC name 3-sec-butyl-1-heptyne is

Explanation of Solution

The name shows that the longest carbon chain should contain seven carbons with a triple bond between C₁ & C₂ and a sec-butyl group on C₃.

Conclusion

The structure corresponding to the IUPAC name 3-sec-butyl-1-heptyne is

Interpretation Introduction

h) 5-tert-Butyl-2-methyl-3-octyne.

Interpretation:

The structure of 5-tert-Butyl-2-methyl-3-octyne is to be drawn.

Concept introduction:

The longest carbon chain containing the triple bond to be chosen. Based on the name of the parent compound–the alkyne name ends with the suffix–yne. The chain is to be numbered from the end that gives the lowest number to the carbon in triple bond. Substituents are to be numbered according to their positions in the chain and listed alphabetically. The position of the triple bond is indicated by giving the number of the first alkyne carbon before the name of the parent name. If more than one triple bond is present, their positions are indicated with the suffixes -diyne, -triyne and so on.

To draw:

The structure corresponding to the IUPAC name 5-tert-Butyl-2-methyl-3-octyne.

Answer to Problem 27AP

The structure corresponding to the IUPAC name 5-tert-Butyl-2-methyl-3-octyne is

Explanation of Solution

The name shows that the longest carbon chain should contain eight carbons with a triple bond between C₃ & C₄, a tert-butyl group on C₅ and a methyl group on C₂.

Conclusion

The structure corresponding to the IUPAC name 5-tert-Butyl-2-methyl-3-octyne is