Radicofunctional Nomenclature

Rule C-21

21.1 - One characteristic group in the compound is expressed as one word (called the "functional class name"), as shown in Table C-IV . Provided that this group is univalent, the remainder of the molecule attached to that group is expressed in its radical form as another word which precedes the functional class name.

Example to Rule C-21.1

Characteristic group, OH: Alcohol (functional class name)
Radical, CH3: Methyl
Complete name: Methyl alcohol

Note: In English and French the functional name and the radical are named as separate words. The radical name has adjectival significance; so in English the radical name precedes the name of the functional class (methyl alcohol) but in French it may follow it (alcool methylique) . In some other languages the name of the radical precedes that of the functional class name but the whole is written as one word (Methylalkohol).

See Recommendations'93 R-

Radicofunctional Nomenclature
Rule C-22
Rule C-23
Rule C-24


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