Question

What should be the correct IUPAC name for diethylbromomethane? (A) 1-Bromo-1,1-diethylmethane (B) 3 -Bromopentane (C) 1-Bromo-1-ethylpropane (D) 1-Bromopentane

Short answer

The correct IUPAC name for diethylbromomethane is (A) 1-Bromo-1,1-diethylmethane.

Step-by-step solution

Build the Structure of Diethylbromomethane

First, let's draw the structure of diethylbromomethane. It consists of two ethyl groups (C2H5) which are bonded to a central carbon atom along with a bromine atom. The structure looks like this: C / \ H3C-C-H | | Br H / \ H3C-C-H | H

Analyze the Options

Now, let's analyze the given options to see which one correctly represents the structure of diethylbromomethane. (A) 1-Bromo-1,1-diethylmethane: In this option, it suggests that there are 1 bromo and 2 ethyl groups attached to a methane group (CH3). This is the correct representation of the structure we just built. (B) 3-Bromopentane: In this option, it suggests that there is a bromine atom attached to the third carbon of a five-carbon chain (pentane). This does not match the structure of diethylbromomethane. (C) 1-Bromo-1-ethylpropane: In this option, it suggests that there is a bromo and an ethyl group attached to the first carbon of a three-carbon chain (propane). This does not match the structure of diethylbromomethane. (D) 1-Bromopentane: In this option, it suggests that there is a bromine atom attached to the first carbon of a five-carbon chain (pentane). This does not match the structure of diethylbromomethane.

Make a Conclusion

Based on the analysis of the given options and the correct structure of diethylbromomethane, the correct IUPAC name for diethylbromomethane is (A) 1-Bromo-1,1-diethylmethane.

Key concepts

Organic Chemistry Nomenclature

In organic chemistry, nomenclature is the systematic method used to name chemical compounds. This ensures that every compound has a unique and universally understood name. The International Union of Pure and Applied Chemistry (IUPAC) lays down rules for this nomenclature.
These rules help in avoiding confusion and ensure that chemists across the globe have a standard language. Key rules include:

• Identifying the longest carbon chain and naming it using standard alkane names (methane, ethane, propane, etc.).
• Numbering the chain to give substituents (like functional groups) the lowest possible number.
• Naming substituents and prefixes alphabetically when writing the compound name.

For instance, when identifying and naming diethylbromomethane, one must focus on these naming conventions to select the correct IUPAC name. Naming such compounds accurately ensures that the molecular structure and additional substituents are properly communicated.

Bromine-Containing Compounds

Bromine is a significant element in organic chemistry. When it appears in organic compounds, it's often referred to as a 'haloalkane' or 'alkyl halide.' These are alkanes with one or more hydrogen atoms replaced by halogen atoms like bromine. In naming these compounds:

• Use the prefix 'bromo-' to indicate the presence of a bromine atom.
• Position matters, so indicate the carbon to which bromine is attached by counting from the nearest end of the carbon chain.

This approach is crucial because the physical and chemical properties of the compound can significantly change depending on the bromine placement. In the case of diethylbromomethane, knowing where the bromine atom is attached helps in finding its IUPAC name as 1-Bromo-1,1-diethylmethane.

Carbon Chain Structures

Carbon chains form the backbone of organic molecules. The length and composition of these chains determine the basic framework of a compound. They can appear as:

• Straight chains, where each carbon is linked like a string.
• Branched chains, where additional carbon groups protrude from the main chain.

Branching significantly influences compound properties. That's why knowing the structure of carbon chains helps in deducing the correct nomenclature. For example, in diethylbromomethane, the carbon arrangement forms a branched chain due to the two ethyl groups attaching to the central carbon. Initially recognizing these types of structures ensures accurate IUPAC names and reflects the compound’s chemical behavior. Understanding these branches helps in visualizing and predicting molecular geometry, bonding, and reactivity.