Draw structures of the following derivatives.
(g) the (E) isomer of the ethyl imine of propiophenone

Verified step by step guidance

1. Understand the problem: You are tasked with drawing the (E) isomer of the ethyl imine derivative of propiophenone. This involves forming an imine functional group and ensuring the (E) configuration is achieved.
2. Recall the structure of propiophenone: Propiophenone is an aromatic ketone with the structure C₆H₅-CO-CH₂-CH₃. The ketone group (-CO-) is the reactive site for imine formation.
3. Understand imine formation: An imine is formed by the reaction of a ketone or aldehyde with a primary amine. In this case, ethylamine (CH₃-CH₂-NH₂) reacts with the ketone group of propiophenone, replacing the oxygen atom with a -N=CH-CH₂-CH₃ group.
4. Determine the (E) configuration: The (E) isomer refers to the trans configuration of the imine double bond. This means the substituents on either side of the C=N bond must be on opposite sides. For the imine of propiophenone, the phenyl group (C₆H₅) and the ethyl group (CH₂-CH₃) should be on opposite sides of the C=N bond.
5. Draw the structure: Start with the phenyl group (C₆H₅) attached to the carbon of the C=N bond. On the other side of the C=N bond, place the ethyl group (CH₂-CH₃) trans to the phenyl group. Complete the structure by attaching the ethylamine-derived nitrogen atom to the C=N bond and ensuring all valencies are satisfied.

Key Concepts

E/Z Isomerism

E/Z isomerism is a type of stereoisomerism that occurs in alkenes and other compounds with restricted rotation around a double bond. The 'E' (from the German 'entgegen') designation indicates that the highest priority substituents on either side of the double bond are on opposite sides, while 'Z' (from 'zusammen') indicates they are on the same side. Understanding this concept is crucial for accurately drawing the correct isomer of a compound.

Imine Formation

Imine formation is a reaction between a carbonyl compound (like an aldehyde or ketone) and an amine, resulting in the creation of an imine. This process involves the nucleophilic attack of the amine on the carbonyl carbon, followed by dehydration to eliminate water. Recognizing how imines are formed helps in understanding the structure of the ethyl imine derived from propiophenone.

Propiophenone Structure

Propiophenone is an aromatic ketone with the structure C6H5C(O)C2H5, where a phenyl group is attached to a carbonyl group, which is further connected to an ethyl group. This structure is essential for understanding the derivatives formed from it, including the ethyl imine. Familiarity with the parent compound's structure aids in visualizing and drawing its derivatives accurately.