Trithiocarbonic acids

Another boron sulfide, of stoichiometry BS2, can be made by heating B2S3 and sulfur to 300°C under very carefully defined conditions. It is a colourless, moisture-sensitive material with a porphine-like molecular structure, BgSig, as shown in Fig. 6.29b. An alternative route to BgSie involves the reaction of dibromotrithiadiborolane with trithiocarbonic acid in an H2S generator in dilute CS2 solution ... 

Thio-germaniumsaure, /. thiogermanic acid, -harnstoff, m. thiourea, -kohlensaure, /. thiocarbonic acid, specif, trithiocarbonic acid. H CSa. 

Triazolopyridine-3-thiols (or thiones) (71) are obtained from the hydrazine and carbon disulfide112 114, thiophosgene,1118 or trithiocarbonic acid.115... 

If concentrated hydrochloric acid is used instead of formic acid in the foregoing preparation, the resulting red liquid consists of a solution of sulphur in trithiocarbonic acid which dissolves quietly in acetone to give a yellow solution, the dissolved sulphur then gradually precipitating out. 

Add decomposes the thiocarbonate to give unstable oily trithiocarbonic acid which dissociates into carbon disulfide and hydrogen sulfide. 

Carbon disulfide is a valuable synthon (see Chapter 9, p. 147) which can be used for the synthesis of thiocarbonic acid derivatives. Thus, carbon disulfide reacts with ammonium polysulfide or hydrogen sulfide to give trithiocarbonic acid (70) or symmetrical esters (73) after reaction with an alkyl halide. With alkoxides or thiolates, carbon disulfide forms xanthates (77) or S-alkyl trithiocarbonates the latter by further treatment with alkyl, acyl or diazonium halides affords the derivatives (74)-(76) (Scheme 39). 

A problem 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, tetrathiophosphate, etc., which appear to be additive names but are incorrect as such because the ligand prefix is now sulfido or sulfanediido [thus giving trisulfidocarbonate(2—),tetrasulfidophosphate(3—), etc.]. Section P-65.2 of Ref. 1 prescribes the infix-based name carbonotrithioic acid, leading to the anion name carbonotrithioate, which will not be mistaken for an additive name. 

C3H4S3 Trithiocarbonic acid, cyclic ethylene ester 822-38-8... 

Only the last of these, trithiocarbonic acid, is known in the free state,741 the others existing only as salts, chlorides, esters, and amides. In the light of modern practice, these acids are here named thio-, dithio-, and trithio-car-bonic acid according to the number of sulfur atoms present in the molecule the hypothetical acids may be distinguished by 5- and/or O-prefixes, e.g., the first is thiocarbonic 0,5-acid and the third is dithiocarbonic 5,5-acid for derivatives of these acids, O- and 5-prefixes are also used, when necessary, before the names of atoms or groups replacing hydrogen of the acid. 

The alkyl thiocarbonates are derived from dithiocar-bonic acid, HO.CS.SH, or trithiocarbonic acid, HS.CS.SH. Carbon disulphide reacts with sulphides to form salts analogous to the carbonates, which are formed by the union of carbon dioxide and metallic oxides —... 

Esters of trithiocarbonic acid are formed from inorganic salts of the acid in the usual way —... 

Lead acetate/triethylamine Trithiocarbonic acid esters from mercaptans and carbon disulfide... 

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