Page 104 - Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005)

IR-6.2 S U B S T I T U T I V E N O M E N C L A T U R E

Unambiguous parent names for non-carbon-containing heteronuclear chains can be derived
from a h ydrocarbon parent or a n on-carbon homonuclear chain parent (cf. S ection IR-6.2.2.1).
Alternatively, heteronuclear c hains may be named additively b y t he method described in
Section IR-7.4. H owever, such names cannot be used as parent names in substitutive
nomenclature.

Example:
4.
1 2 3 4 5
SiH 3 SiH 2 SiH 2 GeH 2 SiH 3
1,2,3,5-tetrasila-4-germapentane (not 1,3,4,5-tetrasila-2-germapentane), o r
2-germapentasilane (note: based on different numbering), or
1,1,1,2,2,3,3,4,4,5,5,5-dodecahydrido-4-germy-1,2,3,5-tetrasily-[5]catena

IR-6.2.4.2 Hydrides consisting of chains o f a lternating skeletal atoms

Chain hydrides with a b ackbone of alternating atoms of two e lements A a nd E, neither of
which is carbon, i.e. of sequences (AE) n A, where element A o ccurs later in the sequence of
Table VI, can be named by successive citation of the following name parts:

(i) a m ultiplicative prefix (Table IV) denoting the number of atoms of element A, with no
elision of a t erminal vowel of this prefix;
(ii) replacement prefixes ending in ‘a’ (Table X) denoting elements A a nd E i n t hat order
(with elision of the terminal ‘a’ of the replacement prefix before another ‘a’ or an ‘o’);
(iii) the ending ‘ne’.

Examples:

tetrastannoxane
1. SnH 3 OSnH 2 OSnH 2 OSnH 3
tetrasilathiane
2. SiH 3 SSiH 2 SSiH 2 SSiH 3
triphosphazane
3. PH 2 NHPHNHPH 2
4. SiH 3 NHSiH 3 disilazane
5.
1 2 3 4 5 6 7
PH 2 N¼PNHPHNHPH 2 tetraphosphaz-2-ene
The first four structures a re parent hydrides, but not the unsaturated compound (see remarks
in Section IR-6.2.2.3).

IR-6.2.4.3 Heteronuclear monocyclic p arent hydrides; H antzsch–Widman nomenclature

For heteronuclear monocyclic parent hydrides there are two general naming systems a nd, in
certain cases, a t hird possibility.

(i) In the (extended) Hantzsch–Widman (H–W) system (Section P-22.2 of Ref. 1), names
are constructed so as to convey the ring s ize, the presence of heteroatoms (i.e. non-carbon
atoms) and the degree of hydrogenation (either mancude, i.e. with the maximum number
of non-cumulative double b onds, or saturated) by means of characteristic prefixes a nd

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