Revised Nomenclature for Radicals, Ions, Radical Ions and Related Species
(IUPAC Recommendations 1993)

RC-83.4. Multiple anionic centers

Continued from RC-83.2. Anionic compounds with anionic centers derived formally by the addition of a hydride ion

Contents of this section

RC-83.4. Multiple anionic centers.

RC-83.4.1. Polyanions identically derived at different positions on the same parent hydride are named using appropriate numerical prefixes and operational suffixes as given in RC-83.1.2 and RC-83.2.

RC-83.4.2. "Ide" and "uide" centers in the same parent hydride. Anionic compounds with two or more anionic centers in the same parent hydride structure, at least one of which is derived formally by the removal of a hydron from a skeletal position, and one by the addition of a hydride ion at another skeletal position, are named by replacing the final "e" of the name of the parent hydride, if present, by the operational suffix "-ide", followed by the operational suffix "-uide", each preceded, where necessary, by the appropriate numerical or multiplicative prefix (see RC-83.1.2.1 and RC-83.2). The "e" of the "-ide" suffix is elided before "-uide" unless a multiplicative prefix precedes the latter. Where there is a choice, low locants of the parent hydride are assigned first to the anionic centers regardless of type and then to "-uide" anionic centers.

Example:

2,4-dihydro-2,2-dimethylcyclopenta[c]borol-4-id-2-uide
RC-83.4.3. Polyanions identically derived from hydroxy characteristic groups or chalcogen analogs by the loss of the hydrogen atom as a hydron from each of two or more hydroxy groups or chalcogen analogs attached to a parent hydride are named by adding a suffix such as "-bis(olate)", or "-tris(thiolate)" to the name of the parent hydride.

Note: The multiplicative prefixes "bis-", "tris-", etc. are used to avoid the possibility of ambiguity which would result if a suffix such as "-diolate" were to be interpreted as describing a monoanion derived from a diol.
Examples:

cyclohexane-1,4-bis(olate)
naphthalene-2,6-bis(thiolate)
RC-83.4.4. Anionic characteristic groups on anionic parent hydrides. Polyanions with anionic centers both in the parent hydride part of the structure and on a characteristic group that may be expressed as an anionic suffix (see RC-83.1.3 through RC-83.1.5) may be named by adding the anionic suffix to the name of a parent anion formed according to Rules RC-83.1.2 and RC-83.2. Where there is a choice, preference for low locants goes to the anionic skeletal atom.

Examples:

cyclohexan-1-ide-4-sulfonate
pent-1-yn-1-id-5-oate
RC-83.4.5. Assemblies of parent anions. Anionic compounds with anionic centers derived from the same parent hydride, but located in different parts of a structure are named, if possible, according to the principles for naming assemblies of identical units (ref 2q) using the multiplicative prefixes "bis-", "tris-", etc., where necessary.

Note: The multiplicative prefixes "bis-" and "tris-",. etc., are used to avoid the possibility for confusion that could arise from the use of the numerical prefixes "di-", "tri-", etc.
Examples:

1,4-phenylenebis(phosphanide)
tetracyano[3-dicyanomethylidene)cycloprop-1-ene-1,2-diyl]dimethanide
(IUPAC multiplicative method; see RC-80.11)
[3-(dicyanomethylidene)cycloprop-1-ene-1,2-diyl]bis[dicyanomethanide]
(CAS multiplicative method; see RC-80.11)
RC-83.4.6. Other polyanions with anionic centers on characteristic groups. Anionic compounds with two or more anionic centers identically derived from the same characteristic group, except for diacids and polyacids, dialcohols and polyalcohols or phenols and their chalcogen analogs (for which see RC-83.1.3, RC-83.1.4.2, and RC-83.4.3), and diimides and polyimides, are named, if possible, on the basis of an anionic parent hydride according to the principles for naming assemblies of identical units (ref 2q) using the multiplicative prefixes "bis-", "tris-", etc., instead of the numerical prefixes "di-", "tri-", etc., where necessary.

Note: Accordingly, anionic centers derived from two or more of such same characteristic groups are not described in terms of such characteristic groups using appropriate multiplicative prefixes.
Examples:

-O-O-CH2-CH2-O-O-ethylenebis(dioxidanide)
1,4-phenylenebis(disulfanide)
propane-1,3-diylbis(amide)
propane-1,3-diylbis(azanide)
Polyanions derived from diimides and polyimides are named on the basis of heterocyclic parent anions in accordance with RC-83.1.2.

Example:

1,3,5,7-tetraoxo-1,2,3,5,6,7-hexahydrobenzo[1,2-c:4,5-c']dipyrrole-2,6-diide
(see RC-83.1.2.2)
1,3,5,7-tetraoxo-5,7-dihydrobenzo[1,2-c:4,5-c']dipyrrole-2,6(1,3H)-diide
(see RC-83.1.2.2)
RC-83.4.7. Anionic centers in both parent compounds and substituent groups. A polyanion in which not all anionic centers can be included in an anionic parent hydride or parent compound (or where it may not be desirable to do so) is named by selecting the part of the structure that includes most of the anionic centers [see RC-83.4.7.4(a)] as the anionic parent hydride or parent compound to be named by the principles of these recommendations. Parts of the structure containing the other anionic centers are then expressed by prefixes as described in the following subsections.

RC-83.4.7.1. Prefixes for anionic centers derived from acid characteristic groups by removal of the hydrogen atoms from all hydroxy, thiol, etc., groups of an acid characteristic group or a chalcogen analog, and that are attached to the parent structure by a single bond are named by changing the "-ic acid" ending of the name of the acid suffix or parent mononuclear oxo acid to "-ato" (ref 2vv, 4u).

Note: In the 1979 IUPAC Organic Rules, these prefixes (ref 4u) were not limited to attachment by a single bond.
Examples:

-CO-O-carboxylato
-SO2-O-sulfonato
-PO(O-)2phosphonato
-AsH(O)(O-)arsinato
Note: In the 1979 IUPAC Organic Rules, this prefix (ref 4u) was used for the anionic substituent group =As(O)-O-
RC-83.4.7.2. Prefixes for anionic chalcogen atoms may be derived by replacing the final "e" of the name of the corresponding monoatomic anion (ref 6h) with an "o" (ref 2ww).

Example:

-O-oxido
RC-83.4.7.3. Systematically derived prefixes for expressing anionic structural units as substituents are formed by replacing the final "e" of the name of the parent anion derived according to RC-83.1.2 with an operational suffix, "-yl" or "-ylidene" or by adding an operational suffix such as "-diyl" to the parent anion name. Where there is a choice, low locant numbers are assigned to the point of attachment to the parent structure.

Examples:

-CH2-methanidyl
-NH2-amidyl
azanidyl
-N2-imidyl
azanediidyl
-PH-phosphanidyl
-BH3-boranuidyl
=N-amidylidene (see RC-80.5)
azanidylidene (see RC-80.5)
azanidediyl (see RC-80.5)
Note: The use of "-diyl" with the anion name "amide" is not recommended.
-S-S-disulfanidyl
cyclohexa-2,5-dien-4-id-1-ylidene
(see RC-80.5)
cyclopenta-1,4-dien-3-ide-1,2-diyl
(see RC-80.5)
2H-benzo[c]borol-2-uid-2-ylidene
(see RC-80.5)
2H-2-benzoborol-2-uid-2-ylidene
(ref 3h) (see RC-80.5)
RC-83.4.7.4. Choice of parent anionic structure. Although, in theory, any portion of a polyanionic structure that can be named by the principles of these recommendations can be the parent structure, it is often useful to have a few guidelines for making this choice. Thus, when necessary, or desirable, a parent anionic structure may be chosen by applying the following criteria in order until a definitive choice is achieved.

(a) the maximum number of anionic centers of any kind, including anionic suffix groups;
Note: This is in agreement with the principles for choosing a preferred component in naming fused heterocyclic ring systems (ref 3i).

(b) the maximum number of senior anionic centers, according to the nature of the anionic atoms, in the same order as the corresponding replacement prefixes (ref 3d, 11). error details
Further choice, if necessary, is made by applying the general criteria for chains and rings given in the 1979 IUPAC Organic Rules (ref 2cc).

Examples:

4-[(4-sulfonatophenyl)azo]benzoate
3-oxidonaphthalene-2-carboxylate
(5-carboxylato-2-thienyl)methanide
References for this section

1. International Union of Pure and Applied Chemistry. Organic Chemistry Division. Commission on Nomenclature of Organic Chemistry, Nomenclature of Organic Chemistry, Sections A, B, C, D, E, F and H, 1979 ed., Pergamon Press, Oxford, 1979, 559 p.

2. Reference 1, Section C, pp. 79-322: [q] Rules C-72, p. 130-1; and C-73, p. 132; [w] Rule C-106.2, p. 146; [cc] Subsections C-0.13, pp. 97-101; and C-0.14, pp. 101-5; [ww] Rule C-86.2, p. 142.

3. Reference 1, Section B, pp. 53-76: [d] Rule B-1.1, pp. 53-5, Table I, p. 53; [h] Rule B-3.5, pp. 67-8; [i] Rules B-6. pp. 71-2; B-10.1 (in part), p. 72; and B-11 (in part).

4. Reference 1, Section D, pp. 323-471: [u] Rule D-5.52, p. 396.

6. International Union of Pure and Applied Chemistry. Inorganic Chemistry Division. Commission on Nomenclature of Inorganic Chemistry, Nomenclature of Inorganic Chemistry, Recommendations 1990, G. J. Leigh, ed., Blackwell Scientific Publications, Oxford, England, 1990, 289 p. [h] Section I-8.3.2, p. 108.

11. International Union of Pure and Applied Chemistry. Organic Chemistry Division. Commission on Nomenclature of Organic Chemistry, Revision of the Extended Hantzsch-Widman System of Nomenclature for Heteromonocycles, Recommendations 1982, Pure Appl. Chem. 55, 409-16, 1983.

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