Bring the power of IUPAC naming to your desktop!

ACD/Name (Chemist Version) offers a standardized set of features for quick and simple generation of IUPAC names, and structures from names. It is a streamlined version of our popular ACD/Name software.

View a full description and pricing on our web store.

Free Radicals, Ions, and Radical Ions

Anions Rule C-84

84.1 - In names of anions formed by loss of a proton from an acid, "-ate" replaces "-ic acid".

Examples to Rule C-84.1

84.2 - Anions formed by loss of a proton from an alcohol or phenol have names ending in "olate" or "oxide", as described in Rule C-206. Those formed from a thiol have names ending in "thiolate" or "sulfide", as described in Rule C-511.3.

84.3 - Anions formed by removal of a proton or protons from a carbon atom are named by adding "-ide", "-diide", etc., to the name of the parent compound, with elision of terminal "e" (if present) before a vowel. Such ions are termed generically "carbanions".

Examples to Rule C-84.3

Exception: Metal derivatives of acetylene are named "acetylides", as, for instance:

Note: Names such as butyllithium and phenylsodium are commonly used and are retained. (See Subsection D-3)

84.4 - Radical anions that may be considered to be formed by loss of a proton from a radical are named by changing the ending "-yl" of the name of the radical to "-ylide" or by adding the word "anion" to the name of the corresponding substance.

Examples to Rule C-84.4

The following names are retained:

See Recommendations'93 R-5.8.3

Two or More Kinds of Ionic Centre with the Same Kind of Charge in a Single Structure
Rule C-85
Rule C-86
Positive and Negative Ionic Centres in a Single Structure
Rule C-87


This HTML reproduction of Sections A, B and C of IUPAC "Blue Book" is as close as possible to the published version [see Nomenclature of Organic Chemistry, Sections A, B, C, D, E, F, and H, Pergamon Press, Oxford, 1979. Copyright 1979 IUPAC.] If you need to cite these rules please quote this reference as their source.

Published with permission of the IUPAC by Advanced Chemistry Development, Inc.,, +1(416)368-3435 tel, +1(416)368-5596 fax. For comments or suggestions please contact