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R-0.2.3 Names

R- Trivial name: a name having no part used in a systematic sense.

Example to R-

Urea (R-9.1, Table 31(a))

R- Semisystematic name or semitrivial name: a name in which at least one part is used in a systematic sense.

Examples to R-

Glycerol (ol) (R-9.1, Table 26(a))

Acetone (one) (R-9.1, Table 27(a))

Styrene (ene) (R-9.1, Table 19(a))

5-Cholestane (ane) (R-2.4.6)

R- IUPAC name: a name formed according to the procedures described in Section A, B, C, D, E, F, and H, of the 1979 edition of the IUPAC Nomenclature of Organic Chemistry as modified by these recommendations (see also R-1). There are several kinds of IUPAC names according to the type of nomenclature operation involved (see R-1.2).

R- Fusion name: a composite name for a polycyclic parent structure having the maximum number of noncumulative double bonds and at least one ortho fusion. Name formation involves the dissection of the structure into contiguous components having recognized trivial or semisystematic names, one of which is selected as the "base component". Attachment of the other component(s) is described by prefixes (see R-2.4.1.).

Examples to R-

Dibenzo[b,e]oxepine (R-2.4.1)

Thieno[3,2-b]furan (R-2.4.1)

R- Hantzsch-Widman name: a name for a heteromonocyclic parent hydride having no more than 10 ring members formed by the citation of "a" prefixes denoting the heteroatoms followed by an ending (the "stem") defining the size of the ring (see R-2.3.3).

1,3-Dithiolane (R-2.3.3)

1,4-Thiazepine (R-2.3.3)

R- Functional class name: a name that expresses a characteristic group as a class term written as a separate word following the name of a parent structure or a name derived from a parent structure. In the latter case, when the derived name is that for a substituent group (formerly called a "radical"), the method has been called "radicofunctional nomenclature" (see R-

Examples to R-

Methyl iodide (R-5.3.1)

Ethyl alcohol (R-

Ethyl methyl ketone (R-

Acetyl chloride (R-5.7.6)

Trimethylarsane sulfide (R-

Propanal hydrazone (R-

Ethyl acetate (R-

R- Radicofunctional name: see under "Functional class name".

R- Replacement name: a name in which the replacement of an atom or a group of a parent structure by another atom or group is indicated by affixes attached to or inserted into the name of the parent structure. There are two main types of replacement names.

(a) Skeletal replacement name: a name in which the replacement of skeletal atoms and their associated hydrogen atom of a parent hydride by other atoms with the appropriate number of hydrogen atoms is indicated by nondetachable prefixes. When carbon atoms are replaced by heteroatoms (see R-1.2.2), this method has been called "a" nomenclature, since the prefixes used end in "a".

Examples to R-

Silacyclohexane (R-

2,7,9-Triazaphenanthrene (R-

Certain names in which the prefix "thio-", "seleno-", or "telluro-" indicates replacement of a skeletal oxygen atom by a sulfur, selenium, or tellurium atom, respectively, are also skeletal replacement names.

Examples to R-

2H-Thiopyran (R-

(b) Functional replacement name: a name containing prefixes or infixes which indicate the replacement of an oxygen atom or hydroxy group of a characteristic group, functional parent, or class name by other atom or groups.

Examples to R-

Selenobenzoic acid (R-

Hexane(dithioic) acid (R-

Methyl P,P-dimethylphosphinimidate (R-

R- Substitutive name: a name which indicates the exchange of one or more hydrogen atoms attached to a skeletal atom of a parent structure or to an atom of a characteristic group for another atom or group, which may be expressed by a suffix or by prefixes (see R-1.2.1).

Examples to R-

9,10-Diphenylanthracene (R-5.1.1)

Butane-1,4-diol (R-

Ethylphosphonic acid (R-

N-Methylbezamide (R-

R- Conjunctive name: a name for assemblies of functionalized acyclic parent hydrides and cyclic systems implying the loss of an appropriate number of hydrogen atoms from each (see R-1.2.4)

Examples to R-

Cyclohexaneethanol (R-

Benzene-1,3,5-triacetic acid (R-

R- Additive name: a name that describes:

(a) the formal assembly of names for the components of a compound without loss of atom or groups of atoms from any component, as in the following:

Functional class name:

Styrene oxide (R-

Methyl iodide (R-5.3.1)

Ethyl methyl ether (R-5.5.4)

Ring assembly names:

Biphenyl (R-2.4.4)

2,2'-Bipyridyl (R-2.4.4)

Acyclic "assembly" name:

Biacetyl (R-9.1, Table 27(a))

Salt name:

Calcium diacetate (R-

[2-(Ethoxycarbonyl)ethyl]trimethylammonium bromide (R-

Compound substitutive or multiplicative prefixes:

Pentyloxy (R-5.5.2)

Methylenedioxy (R-5.5.2)

(b) the addition or attachment of atoms or groups of atoms, as illustrated by the following:

Skeleton modifying name:


Prefixes or suffixes that increase the number of substitutable hydrogen atoms of a parent hydride, such as hydro- and -ium:

Examples to R-

2,3,4,5-Tetrahydroazocine (R-3.1.2)

Pyridinium (R-

R- Subtractive name: a name for a modified parent structure in which prefixes and/or suffixes indicate the removal of atom or groups and, where required, replacement by an appropriate number of hydrogen atoms (see R-1.2.5).

Prefixes: de-, anhydro-, nor-.

Suffixes that decrease the number of substitutable hydrogen atoms of a parent structure: -ene, -yne, -ylium, -yl, -ide.

Examples to R-

Demethylmorphine (R-

3-Norlabdane (R-

Hex-2-ene (R-3.1.1)

Methyl (R-

R- Multiplicative name: a name that expresses multiple occurrence of identical parent structures, two or more of which are connected by a symmetrical structure expressible by means of a multivalent simple or composite prefix (see R-1.2.8).

Examples to R-

4,4'-Peroxydibenzoic acid (R-5.5.5)

[Oxybis(ethyleneoxy)]diacetic acid (R-4.2.6)

R-0.2.4 Other terms used in these recommendations

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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