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Hydrazines and Their Derivatives

Rule C-921

921.1 - Compounds derived by replacement of hydrogen in hydrazine by groups other than acyl (for which see Rule C-921.5) are named (a) as substitution products of hydrazine or (b), if a group having priority for citation as principal group is also present, by use of the prefix "hydrazino-". The nitrogen atoms are denoted by locants N and N', or 1 and 2. For method (a) numerical locants are the lowest possible, or primes as few as possible; for method (b) the nitrogen atom at the point of attachment is unprimed or has locant 1.

Examples to Rule C-921.1

921.2 - Alternatively, for compounds in which the radicals and are derived from parent molecules that, when unsubstituted, are identical, names may be formed by methods analogous to those used for azo compounds (Rules C-911 and C-912) but with "hydrazo" in place of "azo". The names so obtained are available for indication of further substitution on the nitrogen atoms provided that no ambiguity is caused thereby; when ambiguity would be caused thereby, the compounds are named according to Rule C-921.1.

Examples to Rule C-921.2

(compare Rule C-911.1)
or 3,5'-Hydrazodi-(1-naphthalenesulfonic acid)
(compare Rule C-912.2)

(compare Rule C-911)

(compare Rule C-912)

921.3 - When one nitrogen atom of a hydrazine group forms part of a ring the compound is named as an amino derivative of the heterocycle.

Example to Rule C-921.3

921.4 - A group -NH-NH- attached to a single carbon atom is denoted by a prefix "hydrazi-" when another group having priority for citation as principal group is also present. See, however, Rule B-1.

Example to Rule C-921.4

921.5 - Compounds formed by replacement of hydrogen of a hydrazine group by an acyl group, and their further substitution products, are named by one of the following methods: (a) If a substituent having priority for citation as principal group is also present, the compound is named as an acylhydrazino compound (compare Rule C-921.1); the nitrogen atom attached to the parent carrying the principal group has the locant N (unprimed) or 1. (b) If there is no substituent having priority for citation as principal group, the ending "ic acid" or "-oic acid" of the name of the acid is changed to "-ohydrazide"; or if the ending of the name of the acid is "-carboxylic acid", this is changed to "-carbohydrazide"; the nitrogen atom attached to the acyl group then has the locant N or 1'.

Examples to Rule C-921.5

921.6 - Salts of hydrazines are named as derivatives of hydrazinium(1+) or hydrazinium(2+), according to whether one or both nitrogen atoms bear a charge (see Rule 3.17 of I.U.P.A.C. Nomenclature of Inorganic Chemistry, 1970 ). If only one nitrogen atom bears a charge and it is known which, then that atom has the locant N (unprimed) or 1.

Examples to Rule C-921.6

921.7 - Acyclic polyhydrazines may be named by replacement nomenclature (see Subsection C-0.6).

Example to Rule C-921.7

See Recommendations'93 R-5.6.6, R-

Hydrazines and Their Derivatives C-922, C-923
Diazonium and Ralated Groups C-931
Groups Containing Three or More Contiguous Nitrogen Atoms C-941, C-942
Compounds Containing a N=C-N or N=C=N Group C-951, C-952, C-953, C-954, C-955, C-956
Compounds Containing a N-C(-N)=N Group C-961, C-962
Compounds Containing a N-CO-N or Related Group C-971, C-972, C-973, C-974, C-975
Compounds Containing a N-CO-N-N or More Complex Group C-981, C-982, C-983, C-984, C-985

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.

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