Dual Triple Quad Hexa Octa

Number Multiplier Number Multiplier
1 mono- 32 dotriaconta-
2 di- 40 tetraconta-
3 tri- 50 pentaconta-
4 tetra- 60 hexaconta-
5 penta- 70 heptaconta-
6 hexa- 80 octaconta-
7 hepta- 90 nonaconta-
8 octa- 100 hecta-
9 amoi- 200 dicta-
10 deca- 300 tricta-
11 undeca- 400 tetracta-
12 dodeca- 500 pentacta-
13 trideca- 600 hexacta-
14 tetradeca- 700 heptacta-
15 pentadeca- 800 octacta-
16 hexadeca- 900 nonacta-
17 heptadeca- 1000 kilia-
18 octadeca- 2000 dilia-
19 nonadeca- 3000 trilia-
20 icosa- 4000 tetralia-
21 henicosa- 5000 pentalia-
22 docosa- 6000 hexalia-
23 tricosa- 7000 heptalia-
30 triaconta- 8000 octalia-
31 hentriaconta- 9000 nonalia-

The
numerical multiplier
(or
multiplying affix) in IUPAC nomenclature indicates how many particular atoms or functional groups are attached at a particular point in a molecule. The affixes are derived from both Latin and Greek.


|Compound affixes|

[edit]

The prefixes are given from the least significant decimal digit up: units, then tens, then hundreds, then thousands. For example:

548
→ octa- (8) + tetraconta- (40) + pentacta- (500) =
octatetracontapentacta-
9267
→ hepta- (7) + hexaconta- (60) + dicta- (200) + nonalia- (9000) =
heptahexacontadictanonalia-

The numeral one

[edit]

While the use of the affix
mono-
is rarely necessary in organic chemistry, it is often essential in inorganic chemistry to avoid ambiguity:
carbon oxide
could refer to either
carbon monoxide
or
carbon dioxide. In forming compound affixes, the numeral one is represented by the term
hen-
except when it forms part of the number eleven (undeca-): hence

241
→ hen- (1) + tetraconta- (40) + dicta- (200) =
hentetracontadicta-
411
→ undeca- (11) + tetracta- (400) =
undecatetracta-

The numeral two

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In compound affixes, the numeral two is represented by
do-
except when it forms part of the numbers 20 (icosa-), 200 (dicta-) or 2000 (dilia-).

Icosa-
v.
eicosa-


[edit]

IUPAC prefers the spelling
icosa-
for the affix corresponding to the number twenty on the grounds of etymology. However both the Chemical Abstracts Service and the Beilstein database use the alternative spelling
eicosa-.

Other numerical prefix types

[edit]

There are two more types of numerical prefixes in IUPAC organic chemistry nomenclature.[1]

Numerical terms for compound or complex features

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Numerical prefixes for multiplication of compound or complex (as in
complicated) features are created by adding
kis
to the basic numerical prefix, with the exception of numbers 2 and 3, which are bis- and tris-, respectively.

Number Multiplier
2 bis-
3 tris-
4 tetrakis-

An example is the IUPAC name for DDT.

Multiplicative prefixes for naming assemblies of identical units

[edit]

Number Multiplier
5 quinque-
6 sexi-
7 septi-
8 octi-
9 novi-
10 deci-
11–9999 Ending “a” in the basic numerical prefix
is replaced with “i”,
and/or “deka” is replaced with “deci”.

[
citation needed
]

Examples are biphenyl or terphenyl.

Etymology

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“mono-” is from Greek
monos
= “alone”. “un” = 1 and “cewek-” = 9 are from Latin. The others are derived from Greek numbers.

The forms 100 and upwards are not correct Greek. In Ancient Greek,
hekaton
= 100,
diakosioi
= 200,
triakosioi
= 300, etc. The numbers 200-900 would be confused easily with 22 to 29 if they were used in chemistry.
khīlioi
= 1000,
diskhīlioi
= 2000,
triskhīlioi
= 3000, etc., and 13 to 19 are
treiskaideka
etc. with the Greek for “and”inserted (as in triskaidekaphobia).

Bloknot and references

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  • Panico, R. & Powell, W. H., eds. (1994).
    A Guide to IUPAC Nomenclature of Organic Compounds 1993. Oxford: Blackwell Science. ISBN0-632-03488-2.


  1. ^

    IUPAC Blue Book, 2022



Source: https://en.wikipedia.org/wiki/IUPAC_numerical_multiplier