Chapter 15.4, Problem 4QQ

Interpretation Introduction

Interpretation:

IUPAC name for formaldehyde has to be chosen from the given options.

Concept Introduction:

For naming an aldehyde in IUPAC nomenclature, the suffix “-al” is added to the parent alkane name.

IUPAC rules for naming an aldehyde:

• • The longest parent carbon chain is identified that includes the carbonyl group.
• • The parent chain name is changed by replacing the suffix “-e” with “-al”.
• • Numbering is done in a way that the carbonyl group is designated as number 1.  This is not indicated in the part of the name because for aldehyde, the carbonyl carbon is always numbered 1.
• • The identity and location of substituents if any has to be determined and this information has to be added in front of the IUPAC name.
• • If the carbonyl functional group is attached to a ring of carbon atoms, the ring is named and “-carbaldehyde” is added as suffix.

Common names for aldehyde are a single word and not like alcohol or ether which contains two words.  The counting of carbon atoms leads to the naming of aldehyde.  From the total number of carbon atoms present in the given aldehyde, the common name of the aldehyde can be derived.