Thiocarbonate

Monothiocarbonate is the dianion , which has C2v symmetry. Monothiocarbonate arises by the hydrolysis of thiophosgene or the reaction of base with carbonyl sulfide: : The esters of monothiocarbonic acids are called monothiocarbonates as well (e.g. O-ethyl-S-methyl monothiocarbonate ). ==Dithiocarbonates==

Dithiocarbonate is the dianion , which has C2v symmetry. It arises from the reaction of aqueous base with carbon disulfide: : Important derivatives of dithiocarbonates are the xanthates (O-esters of dithiocarbonates), with the formula . These salts are typically prepared by the reaction of sodium alkoxides with carbon disulfide. Another group of dithiocarbonates have the formula . They are often derived by hydrolysis of the corresponding trithiocarbonates (RS)2CS. One example is tetrathiapentalenedione, a heterocycle that consists of two dithiocarbonate groups. ==Trithiocarbonates==

Trithiocarbonate is the dianion , which has D3h symmetry. Trithiocarbonate is prepared by the reaction of sodium hydrosulfide (NaSH) with carbon disulfide: : The relatively elusive trithiocarbonic acid has been characterized by X-ray crystallography. Esters of thiocarbonic acid, such as dimethyl trithiocarbonate () are also called thioxanthate esters. Trithiocarbonate esters inhibit the enzyme carbonic anhydrase. abbreviated Na2dmit is one of several cyclic trithiocarbonates. ==Perthiocarbonates==

Addition of sulfur to trithiocarbonate gives the perthiocarbonate anion , which contains one sulfur–sulfur bond. Perthiocarbonic acid (or tetrathioperoxycarbonic acid / disulfanylmethanedithioic acid / CAS#13074-70-9) has never been obtained in pure form. ==See also==