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How is 4-methylpentanal named using IUPAC rules?
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aldehyde
Alcohols may be oxidized to give aldehydes, ketones, and carboxylic acids. The oxidation of organic compounds generally increases the number of bonds from carbon to oxygen, and it may decrease the number of bonds to hydrogen.
Under IUPAC systematic nomenclature, 4-methylpentanal is named by identifying the longest carbon chain that includes the carbonyl group as the parent alkane.1
The naming process follows these steps:
- Parent Chain: The longest carbon chain contains five carbon atoms, making the parent name "pentane".1
- Suffix: The suffix "-e" is replaced with "-al" to indicate the presence of the aldehyde group.1
- Numbering: The chain is numbered starting from the carbonyl carbon, which is always designated as carbon 1.1
- Substituents: Because the methyl group is attached to the fourth carbon of the chain, it is assigned the number 4, resulting in the name 4-methylpentanal.1
Because the carbonyl group of an aldehyde must be located at the end of the parent chain, its position is inherently carbon 1, and therefore no numerical locant is required to specify its location.1