Organic chemistry with biological applications

John E. McMurry

ISBN #9781285842912

3rd Edition

1,528 Questions

13,325 Students Helped

Homework Questions

Summary

Learning Objectives

Key Concepts

Example Problems

Explanations

Common Mistakes

Summary

This section provides an in-depth exploration of carbonyl condensation and alpha-substitution reactions, covering mechanisms such as aldol condensation, Claisen and Dieckmann condensations, Michael additions, and enamine (Stork) reactions. Fundamental to these transformations is the formation of enols and enolate ions, which serve as key nucleophiles in forming new carbon–carbon bonds. Additionally, the chapter introduces the synthesis and reactivity of amines—integral functional groups in biological compounds and pharmaceuticals. Understanding the mechanistic details of these reactions enables chemists to predict product outcomes and design strategic syntheses, bridging laboratory methods with biochemical pathways.

Learning Objectives

Key Concepts

CONCEPT

DEFINITION

Definition: The study of molecular reactivity via polar covalent bonds where differences in electronegativity create dipole moments, guiding acid–base behavior.

The study of molecular reactivity via polar covalent bonds where differences in electronegativity create dipole moments, guiding acid–base behavior. •

Example Problems

Example 1

Draw structures for the enol tautomers of the following compounds: (a) Cyclopentanone (b) Methyl thioacetate (c) Ethyl acetate (d) Propanal (e) Acetic acid (f) Phenylacetone

Example 2

How many acidic hydrogens does each of the molecules listed in Problem 17.1 have? Identify them.

Example 3

Draw structures for all monoenol forms of the adjacent molecule. Which would you expect to be most stable? Explain.

Example 4

Show how you might prepare pent-1-en-3-one from pentan-3-one.

Example 5

If methanol rather than water is added at the end of a Hell-Volhard-Zelinskii reaction, an ester rather than an acid is produced. Show how you could carry out the following transformation, and propose a mechanism for the ester-forming step.