Question

The $\text{IUPAC}$ name for the following compound is :

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• A. 2, 5-dimethyl-5-carboxy-hex-3-enal
• B. 2, 5-dimethyl-6-oxo-hex-3-enoic acid
• C. 6-formlyl-2-methyl-hex-3-enoic
• D. 2, 5-dimethyl-6-carboxy-hex-3-enal

Answer 1

The correct option is B 2, 5-dimethyl-6-oxo-hex-3-enoic acid

Here, COOH function group has higher priority than CHO and alkene.
Thus, the number is starts from COOH.
The IUPAC name must end in 'oic acid' for COOH functional group.
Hence, the IUPAC name is
2,5-dimethyl-6-oxo-hex-3-enoic acid