Chapter B, Problem B.1P

Interpretation Introduction

(a)

Interpretation:

The root for the given molecule is to be determined.

Concept introduction:

In case of molecules containing a $\text{C=C }$ or $\text{C}\equiv \text{C}$ bond, the longest continuous carbon chain or largest ring that contains the double or triple bond is considered the root. It is possible that the longest carbon chain has more carbons than specified by the root. But the double or triple bond must be a part of the root. The root is named from the name of the analogous alkane or cycloalkane by replacing the suffix ane by ene if a double bond is present. The suffix ane is replaced by yne if a triple bond is present.

Answer to Problem B.1P

The root for the given molecule is cyclohexene.

Explanation of Solution

The given molecule is

In this molecule, the largest ring containing the double bond has six carbon atoms. Hence, the root is cyclohexene, as shown below.

Conclusion

The root is determined from the longest carbon chain or the largest ring containing the double or triple bond between the carbon atoms.

Interpretation Introduction

(b)

Interpretation:

The root for the given molecule is to be determined.

Concept introduction:

In case of molecules containing a $\text{C=C }$ or $\text{C}\equiv \text{C}$ bond, the longest continuous carbon chain or largest ring that contains the double or triple bond is considered the root. It is possible that the longest carbon chain has more carbons than specified by the root. But the double or triple bond must be a part of the root. The root is named from the name of the analogous alkane or cycloalkane by replacing the suffix ane by ene if a double bond is present. The suffix ane is replaced by yne if a triple bond is present.

Answer to Problem B.1P

The root for the given molecule is ethene.

Explanation of Solution

The given molecule is

In this molecule, the double bond is a part of the chain attached to the ring. Although the ring has more carbon atoms than the side chain, the ring does not contain a $\text{C=C }$ bond. Hence, the side chain containing the double bond is the root. It has two carbon atoms. Hence, the root is ethene, as shown below.

Conclusion

The root is determined from the longest carbon chain or the largest ring containing the double or triple bond between the carbon atoms.

Interpretation Introduction

(c)

Interpretation:

The root for the given molecule is to be determined.

Concept introduction:

In case of molecules containing a $\text{C=C }$ or $\text{C}\equiv \text{C}$ bond, the longest continuous carbon chain or largest ring that contains the double or triple bond is considered the root. It is possible that the longest carbon chain has more carbons than specified by the root. But the double or triple bond must be a part of the root. The root is named from the name of the analogous alkane or cycloalkane by replacing the suffix ane by ene if a double bond is present. The suffix ane is replaced by yne if a triple bond is present.

Answer to Problem B.1P

The root for the given molecule is propyne.

Explanation of Solution

The given molecule is

In this molecule, the triple bond is a part of the chain attached to the ring. Although the ring has more carbon atoms than the side chain, the ring does not contain a $\text{C}\equiv \text{C}$ bond. Hence, the side chain containing the triple bond is the root. It has three carbon atoms. Hence, the root is propyne, as shown below.

Conclusion

The root is determined from the longest carbon chain or the largest ring containing the double or triple bond between the carbon atoms.

Interpretation Introduction

(d)

Interpretation:

The root for the given molecule is to be determined.

Concept introduction:

In case of molecules containing a $\text{C=C }$ or $\text{C}\equiv \text{C}$ bond, the longest continuous carbon chain or largest ring that contains the double or triple bond is considered the root. It is possible that the longest carbon chain has more carbons than specified by the root. But the double or triple bond must be a part of the root. The root is named from the name of the analogous alkane or cycloalkane by replacing the suffix ane by ene if a double bond is present. The suffix ane is replaced by yne if a triple bond is present.

Answer to Problem B.1P

The root for the given molecule is hexene.

Explanation of Solution

The given molecule is

In this molecule, the longest carbon chain containing the double bond has six carbon atoms. Hence, the root is hexene, as shown below.

Conclusion

The root is determined from the longest carbon chain or the largest ring containing the double or triple bond between the carbon atoms.