40 Sulfur Compounds (Miscellaneous)
Other chapters have been devoted to the nomenclature of organosulfur acids and their functional derivatives (Chapter 18) and the most common nonacidic carbon-sulfur compounds (Chapter 39). In the present chapter most of the remaining classes of organic sulfur compounds are considered. The majority of these are functional derivatives of inorganic sulfur acids and oxides wherein the central sulfur atom is not directly attached to carbon. A few of the organic derivatives treated in this chapter are named on the basis of parent inorganic structures that have been assigned names not officially recognized in the 1970 IUPAC Inorganic Rules. This practice does not imply a recommendation that these parent names be used generally for the inorganic compounds themselves. Organic thiocyano compounds (RSCN) and isothiocyano compounds (RNCS) are discussed in Chapter 32. Recommended Nomenclature Practice Esters of inorganic sulfur acids are named in the same way as esters of organosulfur acids and carboxylic acids. The first word of the name is that of a cation (other than hydrogen) if one is present; this is followed first by the name of the esterifying group (using the locants O— or S— when necessary to avoid ambiguity) and then by the name of the anion of the parent acid. If more than one cation or esterifying group is present, their names are cited in alphabetical order. In names of partial esters the word hydrogen immediately precedes the anion name. As with other types of esters and salts, each component of the name is a separate word. CH3OSO2OCH3
Dimethyl sulfate
C H SS(0)ONa
Sodium S-phenyl thiosulfite
CH CH OSOH
Ethyl hydrogen sulfoxylate
CH3CH2CH2OSO2SO2OCH3
Methyl propyl dithionate
6
5
3
2
The sulfur amido acids H NS(0)OH and H N S 0 O H are preferably given the parent names sulfinamidic acid and sulfamidic acid, respectively, in 2
2
307
2
308
NOMENCLATURE OF ORGANIC COMPOUNDS
forming names of their organic derivatives. Names of substituting groups (except ammo) attached to the nitrogen atom are cited as prefixes. (CH CH ) NS(0)OH
Diethylsulfinamidic acid
C HsNHS0 OCH
Methyl phenylsulfamidate
3
2
2
6
2
3
HONHS0 OCH CH CH 2
2
2
3
Propyl hydroxysulfamidate
N-Amino derivatives are preferably named analogously to the organosulfur amides (see Chapter 18) by attaching the appropriate functional suffix to the name of the nitrogen chain system. H NNHS(0)OCH CH 2
2
Ethyl diazanesulfinate
3
Organic amides of inorganic sulfur acids are best named by using regularly formed inorganic names for the parent compounds. The locants N and N' are used when ambiguity would otherwise result. CH NHSNH 3
N-Methylsulfoxylic diamide
2
C H NHS0 NHCH CH 6
5
2
2
CH NHS(0)NHOH
3
iV-Ethyl-N'-phenylsulfuric diamide N-Hydroxy-N'-methylsulfurous diamide
3
As recommended above for acids and esters, N-amino derivatives are best treated as nitrogen chains carrying functional groups (see Chapter 32). C H NHNHS0 NHCH 6
s
2
3
N-Methyl-2-phenyldiazanesulfonamide
Organic derivatives of HN=S(0) and HN=S0 are preferably named as substituted inorganic imides. 2
CH CH CH N=S(0)
JV-Propylsulfinyl imide
C H N=S0
N-Phenylsulfonyl imide
3
6
2
2
5
2
Compounds having the generic structure R S X , where X is halogen or some other "negative" group and m + n is greater than 2, are named as organosulfur compounds The organic substituents, R, are cited as prefixes attached to the word sulfur; this is followed by a space and the names of the X groups in anionic form. W
C H SC1 6
5
3
(CH ) SCN 3
5
W
Phenylsulfur trichloride Pentamethylsulfur cyanide
40.
309
Sulfur Compounds (Miscellaneous)
Discussion Most of the compounds considered in this chapter are relatively uncommon and represent classes properly regarded as organic derivatives of inorganic parent structures; they have often been dealt with and named by inorganic principles, and few attempts have been made to systematize their nomenclature. Organic chemists have usually been content to apply organic naming methods to the carbon-containing portion of the molecule, leaving the traditional inorganic parent name intact. In some cases, however, officially recognized inorganic names for parent compounds are not available, usually because these compounds are not known in the free state; here the best solution is to coin a name by analogy or extrapolation. For example, either sulfinamidic acid or sulfinamic acid is a logical name for H NS(0)OH, since both sulfamidic acid and sulfamic acid have been officially approved for H N S 0 O H . Such factors have been taken into consideration in developing the recommendations presented here. 2
2
2
In naming neutral esters of dibasic inorganic sulfur acids, the multiplying prefix di should not be omitted as in "methyl sulfate" for C H O S 0 O C H . Although names of this type have been used in the past by Chemical Abstracts as Subject Index entries for a number of simple esters of common acids, they are not recommended for general use. Both the 1970 IUPAC Inorganic Rules and the 1965 IUPAC Organic Rules specify dimethyl sulfate as the name of the neutral ester; for the partial ester, C H O S 0 O H , the respective recommendations differ only in the form of name—i.e., methyl hydrogensulfate (inorganic version) and methyl hydrogen sulfate (organic version). 3
2
3
3
2
Replacement of OH in inorganic polybasic acids by other functional groups such as CI or N H leads to structures that have been named inconsistently. By inorganic principles the compound C1S0 0H is called chlorosulfuric acid. Organic chemists, applying the practice of substitution for H , have favored "chlorosulfonic acid," thus implying the parent name "sulfonic acid" for H S 0 O H , the hypothetical tautomer of sulfurous acid. However, sulfonic acid has become firmly established in organic nomenclature as a functional suffix denoting the group —S0 OH, as in benzenesulfonic acid. The analogous case involving replacement of OH by N H is even more complicated. While "aminosulforiic acid" for H N S 0 OH has been avoided by inorganic and organic chemists alike, both amidosulfuric acid and sulfamidic acid are recognized in the 1970 IUPAC Inorganic Rules, and sulfamic acid is added as an acceptable alternative in the 1965 IUPAC Organic Rules. Under these circumstances, and taking note of a general trend toward wider acceptance of —amic acid nomenclature, the present recommendation is to use approved inorganic names as far as possible. 2
2
2
2
2
2
2
310
NOMENCLATURE OF ORGANIC COMPOUNDS
The compound H O N H S 0 O H has often been assigned the parent name hydroxylamine-N-sulfonic acid in naming its organic derivatives. The more systematic name Af-hydroxysulfamidic acid is much preferred. Treatment of symmetrically substituted sulfur amides as substituted amines-e.g., N,N'-sulfonylbis(methylamine) for C H N H S 0 N H C H - - i s recognized as an acceptable alternative in the 1965 IUPAC Organic Rules, as is the contracted form sulfamide for the parent compound H N S 0 N H . However, use of the preferred inorganic amide names is recommended here. A similar approach is best taken with inorganic imide derivatives such as RN=S0 , although here again past organic practice has favored the sulfonylamine type of name. The names sulfinyl and sulfonyl are now officially preferred to the older "thionyl" and "sulfuryl" for the groups S(O) and S 0 . The latter forms should not be used in naming organic compounds. 2
3
2
3
2
2
2
2
Table 40.1. Examples of Acceptable Usage 1.
CH CH OS0 OH
Ethyl hydrogen sulfate
2.
C1CH CH 0S(0)C1
2-Chloroethyl chlorosulfite
3.
CH CH CH SS(0)(S)OCH
4.
C H OS0 OS0 OC H
5.
CH OS(0)S(0)OCH
Dimethyl dithionite
6.
C H NHS0 OH
Cyclohexylsulfamidic acid Cyclohexylsulfamic acid
7.
(C H ) NS(0)C1
Diphenylsulfinamidoyl chloride
8.
C H NHS0 NHC H
9.
(CH ) NNHS0 OCH
10.
CH CH OS0 NHS0 OCH
11.
CH
3
2
2
2
3
6
2
2
2
5
2
2
6
3
n
6
2
5
6
2
S
2
3
6
2
2
3
2
2
JV,W-Diphenylsulfuric diamide Af,iV'-Diphenylsu Ifamide
S
Methyl 2,2-dimethyldiazanesulfonate Methyl 2,2-dimethylhydrazinesulfonate
3
2
C H NHS0 NS0 NHC H 2
2
12.
C H CH N=S0
13.
F CSF
14.
C H N=SF
15.
(CH CO) SI
6
5
3
6
2
s
iV-(Phenylmethyl)sulfonyl imide iV-Benzylsulfonyl imide (Trifluoromethyl)sulfur pentafluoride
S
5
3
2
6
Ethyl methyl imidodisulfate 3
N,N'-Diphenyl(methylimido)disulfuric diamide
3
I s
O-Methyl 5-propyl dithiosulfate Diphenyl disulfate
5
3
6
6
3
2
2
4
(Phenylimino)sulfur difluoride Diethanoylsulfur tetraiodide Diacetylsulfur tetraiodide
2
