Predict the products of the following reactions.
(i)

Verified step by step guidance

1. Step 1: Identify the reaction type. This is a Claisen condensation reaction followed by hydrolysis and decarboxylation. The Claisen condensation involves the reaction of an ester with a ketone in the presence of a base to form a β-keto ester intermediate.
2. Step 2: Analyze the reactants. The first reactant is ethyl acetoacetate (CH₃COCH₂COOCH₂CH₃), which is an ester with an acidic α-hydrogen. The second reactant is cyclohexanone, a ketone with an α-hydrogen. The base used is sodium ethoxide (NaOCH₂CH₃), which will deprotonate the α-hydrogen of the ester to form an enolate ion.
3. Step 3: Mechanism of the Claisen condensation. The enolate ion formed from ethyl acetoacetate will attack the carbonyl carbon of cyclohexanone, leading to the formation of a new C-C bond. This results in a β-keto ester intermediate after the elimination of the ethoxide ion.
4. Step 4: Hydrolysis and decarboxylation. The β-keto ester intermediate undergoes hydrolysis in the presence of acid (H₃O⁺), converting the ester group into a carboxylic acid. Upon heating, the carboxylic acid undergoes decarboxylation, releasing CO₂ and forming the final product.
5. Step 5: Predict the product structure. The final product will be a substituted cyclohexanone with the new substituent derived from the ethyl acetoacetate reactant. The exact structure can be determined by tracing the connectivity formed during the Claisen condensation and subsequent steps.

Key Concepts

Reaction Mechanisms

Understanding reaction mechanisms is crucial in organic chemistry as they describe the step-by-step process by which reactants transform into products. This includes identifying intermediates, transition states, and the movement of electrons. Familiarity with mechanisms helps predict the outcome of reactions and the stability of products formed.

Functional Groups

Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. Recognizing functional groups allows chemists to predict reactivity and the types of reactions that can occur. For example, alcohols, carboxylic acids, and amines each have distinct behaviors in chemical reactions.

Stereochemistry

Stereochemistry involves the study of the spatial arrangement of atoms in molecules and how this affects their chemical behavior. It is essential for predicting the products of reactions, especially in cases where chirality or geometric isomerism is involved. Understanding stereochemistry helps in determining the specific isomers that may be produced in a reaction.