Give the products expected when the following tertiary amines are treated with a peroxyacid and heated.
(a) N,N-dimethylhexan-2-amine

Verified step by step guidance

1. Step 1: Recognize that the reaction involves a tertiary amine and a peroxyacid. This is a Cope elimination reaction, which occurs when a tertiary amine oxide is heated, leading to the formation of an alkene and a hydroxylamine.
2. Step 2: Write the structure of N,N-dimethylhexan-2-amine. The nitrogen atom is bonded to two methyl groups and a hexan-2-yl group.
3. Step 3: React the tertiary amine with a peroxyacid (e.g., mCPBA). The peroxyacid oxidizes the tertiary amine to form a tertiary amine oxide. Represent this step as: $R\left(\mathrm{CH}\right)2_N\left(\mathrm{CH}\right)3_O$.
4. Step 4: Heat the tertiary amine oxide. This triggers the Cope elimination, where a concerted mechanism leads to the formation of an alkene and a hydroxylamine. The β-hydrogen (on the carbon adjacent to the nitrogen) is eliminated along with the nitrogen oxide group.
5. Step 5: Identify the product. The elimination occurs to form the most stable alkene, which is determined by Zaitsev's rule (the more substituted alkene is favored). In this case, the product will be 2-hexene (a mixture of E and Z isomers) and dimethylhydroxylamine.

Key Concepts

Tertiary Amines

Tertiary amines are organic compounds that contain a nitrogen atom bonded to three carbon-containing groups. They are characterized by their ability to act as nucleophiles due to the lone pair of electrons on the nitrogen. In reactions, tertiary amines can undergo various transformations, including oxidation and acylation, which are relevant when considering their behavior with peroxyacids.

Peroxyacids

Peroxyacids, also known as peracids, are organic compounds that contain a peroxy group (-O-O-) attached to a carbonyl group. They are strong oxidizing agents and can facilitate the oxidation of amines, leading to the formation of N-oxides. Understanding the reactivity of peroxyacids is crucial for predicting the products formed when they react with tertiary amines.

Oxidation Reactions

Oxidation reactions involve the loss of electrons or an increase in oxidation state by a molecule. In the context of tertiary amines reacting with peroxyacids, the oxidation process typically results in the formation of N-oxides. Recognizing the mechanisms and products of oxidation reactions is essential for predicting the outcomes of the given reaction scenario.