3.8 Compounds with Nitrogen Chains
139
1-[{3-Methylphenylsulfonyl)oxy]2-phenyldiazene 2-oxide
o
II
(SyN, ,.C,
U 'N NMe2
/N, /S03Me
Me03S
'N
N,N- Dimethylthiophen-2-yldiazenecarboxamide
Diazenedisulfonic acid dimethyl ester or
Dimethyl diazenedisulfonate
(Azodisulfonic acid dimethyl ester or
Dimethyl azodisulfonate)
First discrepencies are then already discernible for the covalent isomers of
arenediazonium salts, which are properly named as aryldiazenols by
IUPAC but, contrary to the rules, as arylhydroxydiazanes by Chem. Abstr .
C6HS-N=N-OH
.. e Ell
C6Hs-N=N9.: Na
Systematic name: Phenyldiazenol
Chem. Abstr. Hydroxy(phenyl)diazene
Traditional name: Benzenediazohydroxide
Sodium phenyldiazenolate
Hydroxy(phenyl)diazene,
sodium salt
Sodium benzenediazoate
Yet another treatment is operative in the naming of doubly alkoxy-substituted
diazenes which are denoted as esters of hyponitrous acid by Chem. Abstr.
/N, /OMe
MeO 'N
syst.: Dimethoxydiazene
CA: Hyponitrous acid dimethyl ester
Unfortunately the situation becomes worse still: even if one can come to
terms with the decision to name azo derivatives of nitrogen cycles as
diazenyl-substituted heterocycles - because of the plausible preference of
rings over chains - it remains utterly incomprehensible why the unsubstituted diazenyl group is named as such, whereas its substituted equivalents
are identified as ... ylazo groups.
HN=N-< ~N
4-Diazenylpyridine
< }-N=N-{ ~N
syst.: 4-(Phenyldiazenyl)pyridine
CA: 4-(Phenylazo )pyridine