Principles of Organic Nomenclature

R-1.2.3 Additive operation

The additive operation involves the formal assembly of a structure from its component parts without loss of any atoms or groups. This can be expressed in various ways as follows:

R- By use of an additive prefix

Examples to R-


(hydro = addition of one H atom)

(homo = addition of a CH2 (methylene) group, in this case to expand a ring)
Note: Coordination nomenclature, used extensively in nomenclature for inorganic compounds, is an additive operation.

Examples to R-

(chloro = addition of one Cl atom;
triethylphosphine = addition of one (C2H5)3P ligand group)

R- By use of an additive suffix

Examples to R-


(-ium = addition of one H+)

R- By use of a separate word

R- With the name of a neutral parent structure

Examples to R-


Trimethylarsane sulfide


Styrene oxide

R- With one or more substituent prefix ("radical") name(s) (formerly called radicofunctional nomenclature). Here the separate word is a class or subclass name representing the characteristic group or the kind of characteristic group to which the substituents ("radicals") are linked.

Examples to R-

R- By connecting the names of the components of an addition compound with a dash (long hyphen)

Example to R-

R- By juxtaposition or multiplication of substituent prefix terms

Examples to R-

R-1.2.4 Conjunctive operation
R-1.2.5 Subtractive operation
R-1.2.6 Ring formation or cleavage
R-1.2.7 Rearrangement
R-1.2.8 Multiplicative operation

This HTML reproduction is as close as possible to the published version [see IUPAC, Commission on Nomenclature of Organic Chemistry. A Guide to IUPAC Nomenclature of Organic Compounds (Recommendations 1993), 1993, Blackwell Scientific publications, Copyright 1993 IUPAC]. If you need to cite these rules please quote this reference as their source.

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