Ch. 25 - Amines: Structure, Reactions, and Synthesis

Mullins - Organic Chemistry: A Learner Centered Approach 1st Edition

Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471Not the one you use?Change textbook

Mullins 1st Edition

Ch. 25 - Amines: Structure, Reactions, and Synthesis

Problem 56b

Chapter 24, Problem 56b

Suggest reagents to carry out the following transformations. Some may require more than one step.
(b)

Verified step by step guidance

Identify the starting material and the product. The starting material is 2-bromo-3-methylpyridine, and the product is 2-dimethylamino-3-methylpyridine.

Recognize that the transformation involves replacing the bromine atom with a dimethylamino group. This suggests a nucleophilic substitution reaction.

Consider using a nucleophilic substitution reaction such as the Buchwald-Hartwig amination, which is effective for aryl halides. This reaction typically requires a palladium catalyst, a ligand, and a base.

Select appropriate reagents for the Buchwald-Hartwig amination. A common choice is Pd(OAc)₂ as the catalyst, a phosphine ligand like Xantphos, and a base such as sodium tert-butoxide.

Use dimethylamine as the nucleophile in the reaction. The reaction conditions should facilitate the substitution of the bromine atom with the dimethylamino group, yielding the desired product.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.

Video duration:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Nucleophilic Aromatic Substitution

Nucleophilic aromatic substitution involves the replacement of a leaving group, such as bromine, on an aromatic ring with a nucleophile. This reaction is facilitated by electron-withdrawing groups on the ring, which stabilize the intermediate. In this transformation, the bromine is replaced by an amine group, indicating a nucleophilic substitution process.

Amination

Amination is the process of introducing an amine group into a molecule. In this reaction, the brominated aniline undergoes amination to form a substituted aniline. This typically involves the use of reagents like ammonia or amines, often under conditions that promote nucleophilic attack on the aromatic ring.

Pyridine Ring Chemistry

Pyridine is a basic heterocyclic aromatic organic compound with a nitrogen atom. Its chemistry is influenced by the electron-withdrawing nature of the nitrogen, which affects reactivity and substitution patterns. Understanding pyridine's behavior is crucial for predicting outcomes in reactions involving pyridine derivatives, such as the transformation shown in the image.

Recommended video:

1:07

SNAr Reactions of Pyridine Concept 2

Related Practice

Textbook Question

The Gabriel synthesis is most frequently done with 1° alkyl halides. Why is it less successful with more substituted halides?

1057

views

Textbook Question

Predict the product(s) of the reactions shown.

(b)

1157

views

Textbook Question

The synthesis of ⍺-hydroxy acids can be done starting with amino acids. Suggest a mechanism of the two-step transformation shown. [The alcohol oxygen is the same in the reactant and product.

821

views

Textbook Question

Predict the product(s) of the reactions shown.

(j)

908

views

Textbook Question

The final step in the synthesis of diazoxide, a drug used to treat low blood pressure, is shown here. Suggest a mechanism for this step.

1161

views

Textbook Question