Question

Draw the structure for each compound. a. isopropylbenzene b. meta-dibromobenzene c. 1 -chloro-4-methylbenzene

Short answer

Structural representations are drawn with benzene rings and appropriate substituents: an isopropyl group for isopropylbenzene, two bromines in meta positions for meta-dibromobenzene, and a chlorine and a methyl group at positions 1 and 4 respectively for 1-chloro-4-methylbenzene.

Step-by-step solution

Understand Isopropylbenzene

Recognize that isopropylbenzene is also known as cumene. It consists of a benzene ring with an isopropyl group attached to it. The isopropyl group is a 3-carbon chain with the middle carbon attached to the benzene ring.

Draw Isopropylbenzene

Draw a hexagonal benzene ring to represent the aromatic component. At one vertex of the ring, draw a three-carbon chain (propane) but connect the middle carbon of the chain to the benzene ring, conforming the isopropyl group.

Understand Meta-Dibromobenzene

This compound has two bromine atoms attached to a benzene ring in the meta position, which means the bromines are separated by one carbon on the ring.

Draw Meta-Dibromobenzene

Draw a hexagonal benzene ring. Attach one bromine atom to one vertex of the ring, skip the next vertex, and attach the second bromine atom to the following vertex.

Understand 1-Chloro-4-Methylbenzene

This compound has a chlorine atom and a methyl group attached to a benzene ring. The numbering indicates the chlorine is on the first carbon, and the methyl group is on the fourth carbon.

Draw 1-Chloro-4-Methylbenzene

Draw a hexagonal benzene ring. Attach a chlorine atom at one of the vertices to represent carbon number 1. Count three vertices clockwise and attach a methyl group (CH3) to represent carbon number 4.

Key concepts

Understanding Isopropylbenzene Structure

Isopropylbenzene is a fascinating molecule with significant applications in industries such as the production of phenol and acetone. Its structure can be described in simple terms as a benzene ring with an isopropyl group attached.

The isopropyl group itself consists of a chain of three carbon atoms. The central carbon atom of this isopropyl group is directly bonded to the benzene ring, while the two remaining carbon atoms extend as a branch from the central carbon. It's worth noting that the isopropyl group attached to the benzene ring elevates the molecule's reactivity compared to benzene alone, making isopropylbenzene, also known as cumene, an intermediate in various chemical synthesis processes.

Illustrating the structure, one should draw a hexagonal representation of the benzene, signifying the delocalized electrons within the aromatic ring. Attaching the isopropyl group, maintain focus on the central carbon of the three-carbon chain, ensuring its direct bond to the benzene ring structure.

Meta-Dibromobenzene Structure Basics

Dibromobenzene comes in three isomers, one of which is meta-dibromobenzene where the bromine atoms are situated in the meta position to each other. Understanding the 'meta' designation is essential; it indicates that the bromine atoms are attached to the benzene ring with one carbon atom between them.

When drawing the meta-dibromobenzene structure, you would start with your benzene ring and then attach a bromine atom on one of the vertices. Skipping one carbon, affix the other bromine on the third carbon from the first. This pattern is not arbitrary; the placement of these substituents dictates the molecule's chemical behavior.

In a broader context, the positioning of the bromine atoms in the meta-dibromobenzene affects the molecule’s reactivity, illustrating why understanding the structural nuances of organic chemistry compounds is crucial for predicting their functions and uses.

1-Chloro-4-Methylbenzene and its Structure

1-Chloro-4-methylbenzene, often referred to as p-chlorotoluene, is a derivative of benzene with distinct substituents that define its chemical identity. The '1' and '4' in its name are indicative of the positions of the chlorine atom and the methyl group, respectively.

To sketch this compound, one must be familiar with the numbering mechanism used for aromatic compounds. After drawing the hexagonal shape of the benzene ring, you should mark the position of the chlorine atom at the first carbon. Continuing down the ring, position the methyl group (represented as CH₃) on the fourth carbon atom. This systematic approach to drawing ensures accuracy in depicting the molecular structure of compounds.

Additionally, the presence and position of the chlorine and methyl groups influence the compound’s physical properties and reactivity in organic reactions. For instance, the electron-withdrawing property of the chlorine at position 1 may impact how the molecule participates in electrophilic aromatic substitution reactions.