Understanding the IUPAC Name of CH2-COOH-Br: A Comprehensive Guide

The compound CH2-COOH-Br is a functional derivative of ethanoic acid with a bromine substituent. The IUPAC name for this compound is bromoethanoic acid or bromoacetic acid, which refers to the presence of a bromine atom attached to the ethanoic structure.

Structure and Naming Rules

For the IUPAC naming of organic compounds, the structure must be clear and unambiguous. In the case of CH2-COOH-Br, the presence of the bromine atom (Br) is crucial. The bromine atom is attached to the second carbon atom in the ethanoic chain, leading to the complete molecular structure of the compound: Br-CH2-CHOOH.

2-Bromo-Ethanoic Acid: A Detailed Explanation

The IUPAC name for CH2-COOH-Br is 2-bromo-ethanoic acid. The numbering of carbon atoms in the molecule starts from the side of the carbonyl functional group (the carbon atom bonded to the oxygen with a double bond). Following this rule:

The first carbon atom (leftmost) is numbered 1. The second carbon atom (center) is numbered 2. The third carbon atom (rightmost) is numbered 3.

Hence, the bromine atom is attached to the second carbon atom, making the compound 2-bromo-ethanoic acid.

Alternative Naming: 2-Bromo-1-Ethanoic Acid

Another valid IUPAC name for this compound is 2-bromo-1-ethanoic acid. This name highlights the bromine substituent at the second position and the ethanoic acid functional group. However, it is less common and can lead to confusion. The IUPAC prefers to name the longest carbon chain first, which is why 2-bromo-ethanoic acid is more preferred.

Other Related Functional Groups and Alkanoic Acids

Alkanoic acids, such as ethanoic acid (acetic acid), have a general formula ( text{RCOOH} ), where ( text{R} ) is an alkyl group. The bromine substituent in this case is attached to the second carbon, making it a halogenated alkanoic acid. Other examples include:

2-Chloro-ethanoic acid (2-chloroacetic acid) 2-Iodo-ethanoic acid (2-iodoacetic acid)

Conclusion

In conclusion, the IUPAC name for the compound ( text{CH2-COOH-Br} ) is 2-bromo-ethanoic acid. The bromine atom is attached to the second carbon atom in the ethanoic chain, and the naming convention follows the IUPAC rules for organic compounds. This understanding is crucial for chemists and students alike when dealing with halogenated alkanoic acids and other functional derivatives of carboxylic acids.