Page 147 - Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005)

I N O R G A N I C A C I D S A N D D E R I V A T I V E S IR-8.6

Replacement operation Prefix Infix

amid(o) amid(o)
OH ! NH 2
O ! OO peroxy p eroxo
O ! S t hio thio
O ! Se seleno seleno
O ! Te telluro telluro
OH ! F fl uoro fluorid(o)
OH ! Cl chloro chlorid(o)
OH ! Br bromo bromid(o)
OH ! I i odo iodid(o)
OH ! CN cyano cyanid(o)

Example 5 i n S ection IR-8.1 demonstrates the use of the infixes f or OH ! Cl and
O ! S t o a rrive at the name ‘arsonochloridothioic O-acid’ for the derived parent
HAsCl(OH)S ¼ [AsClH(OH)S], required for naming the organic derivative:

EtAsCl(OH)S ethylarsonochloridothioic O-acid.

Functional replacement names may, of course, be used for the derived parent acids
themselves. However, this amounts to introducing an additional system which is not needed
in inorganic nomenclature. As mentioned above, additive and substitutive nomenclature can
always be used.

Example:
1. HAsCl(OH)S ¼ [AsClH(OH)S]
chloridohydridohydroxidosulfidoarsenic (additive), or
5
chloro(hydroxy)-l -arsanethione (substitutive)

Nevertheless, in Table IR-8.2 several inorganic s pecies are listed w hich can be regarded as
derived from species in Table IR-8.1 by various replacement operations, and for which the
common names are in fact derived by the above prefix method (e.g. ‘thiosulfuric acid’).
A p roblem that would arise with the general use of the prefix variant of functional
replacement names is illustrated by the thio acids. The names trithiocarbonic acid,
tetrathiophosphoric acid, etc., would lead to anion names trithiocarbonate, t etrathiophosphate,
etc., which appear t o b e a dditive names but are incorrect as such because the ligand prefix is
now‘sulfido’or ‘sulfanediido’ [ thusgiving t risulfidocarbonate(2 ),tetrasulfidophosphate(3 ),
etc.]. Section P-65.2 of Ref. 1 p rescribes the infix-based n ame carbonotrithioic acid,
leading to the anion name carbonotrithioate, which will not be mistaken for an
additive n ame.
A f ew examples of other f unctional nomenclature are also included i n T able IR-8.2
(e.g. phosphoryl chloride, sulfuric diamide). T hese particular names are well entrenched and
can still be used, but t his type of nomenclature is not recommended for compounds other
than those s hown. Again, additive and substitutive names may always be constructed, as
exemplified in the Table.

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