Chapter 25, Problem 25.1P

Interpretation Introduction

(a)

Interpretation:

The structure for each of the given thioesters.

Concept Introduction:

Thioesters are sulfur analogs of esters. The S-alkyl or S-aryl thioester has a carbonyl group and a sulfur-linked alkyl or aryl group. The first part of the name indicates that the alkyl or aryl group has bonded to the sulfur atom. The last part of the name indicates the carboxylic acid stem. In common usage, the “S-“prefix is understood, and so, it is not mentioned.

Answer to Problem 25.1P

Explanation of Solution

In the given name cyclohexyl thiobenzoate, the cyclohexyl is the alkyl group which is bonded to the sulfur atom. Thiobenzoate consists of a phenyl ring bonded to the sulfur atom through a carbonyl group. The structure for cyclohexyl thiobenzoate is drawn as below:

Conclusion

The structure for cyclohexyl thiobenzoate is:

Interpretation Introduction

(b)

Interpretation:

The structure for each of the given thioesters.

Concept Introduction:

Thioesters are sulfur analogs of esters. The S-alkyl or S-aryl thioester has a carbonyl group and a sulfur-linked alkyl or aryl group. The first part of the name indicates that the alkyl or aryl group has bonded to the sulfur atom. The last part of the name indicates the carboxylic acid stem. In common usage, the “S-“prefix is understood, and so, it is not mentioned.

Answer to Problem 25.1P

Explanation of Solution

The first part of the name suggests that the isopropyl group must be attached directly to the sulfur atom. The second part of the name suggests that the ester is formed from butanoic acid. In IUPAC nomenclature, “thio-“is inserted before the “ate” suffix in the name of the corresponding oxygen ester. The structure for S-isopropyl butanethioate is shown as below:

Conclusion

The structure for S-isopropyl butanethioate is:

Interpretation Introduction

(c)

Interpretation:

The structure for each of the given thioesters.

Concept Introduction:

Thioesters are sulfur analogs of esters. The S-alkyl or S-aryl thioester has a carbonyl group and a sulfur-linked alkyl or aryl group. The first part of the name indicates that the alkyl or aryl group has bonded to the sulfur atom. The last part of the name indicates the carboxylic acid stem. In common usage, the “S-“prefix is understood, and so, it is not mentioned.

Answer to Problem 25.1P

Explanation of Solution

The first part of the name suggests that the phenyl ring must be attached directly to the sulfur atom. The second part of the name suggests that the ester is formed from the carboxylic acid which contains a cyclohexyl ring. In IUPAC nomenclature, “thio-“is inserted before the “ate” suffix in the name of the corresponding oxygen ester.

The structure for S-phenyl cyclohexanecarbothioate is shown as below:

Conclusion

The structure for S-phenyl cyclohexanecarbothioate is: