Ethylxanthate

Potassium ethylxanthate [140-89-6] M 160.3, m > 215°(dec). Crystd from absolute EtOH, ligroin-ethanol or acetone by addition of Et20. Washed with ether, then dried in a desiccator. 

Treatment of pyridyl carbinol 51 with thionyl chloride leads to the corresponding chloride (52), Treatment of that intermediate with 5-methoxy-2-mercaptobenzimidazole (53), obtained from reaction of 4-methoxy-q-phenylenediamine with potassium ethylxanthate leads to displacement of halogen and formation of the sulfide (54). Finally, oxidation with 3-chloroperbenzoic acid produces the sulfoxide omeprazole (55) fl7]. 

Tris(0-ethyl dithiocarbonato)chromium(III) is obtained as a dark blue crystalline powder which decomposes at 100 to 140°. The indium(III) ethylxanthate complex forms small colorless crystals which decompose at 130 to 150°.16,17 The cobalt (III) ethylxanthate complex is isolated as a dark green crystalline powder whose decomposition temperature determined by use of a thermal balance is 135 to 137° (lit. value, 117° 2 118 to 119°8). These compounds decompose slowly in air and more rapidly when heated in solution. The tripositive chromium, indium, and cobalt complexes are insoluble in water but are soluble in many organic solvents (Table T). 

X-ray powder diagrams obtained by the Guinier method show the tris (O-ethyl dithiocarbonato) complexes of chro-mium(III), indium(III), cobalt(III), iron(III), arsenic(III), and antimony(III) to be isomorphous. Carrai and Gottardi have determined the structure of the arsenic(III)18 and anti-mony(III)19 complexes. Crystallographic data for the cobalt(III) and chromium(III) ethylxanthate complexes are given by Derenzini20 and Franzini and Schiaffino,21 respectively. 

Figure 1.6 Anodic current and floatability of galena as a ftmction of potential in the presence of ethylxanthate at pH = 8 after preparation in oxidizing and reducing environment (Guy and Trahar, 1985)...

Richardson, P. E., Stout, J. V. Ill, Proctor, C. L., Walker, G. W., 1984. Electrochemical flotation of sulphides chalcocite-ethylxanthate interactions. Inter. J. Miner. Process, 12 73 - 93 Richardson, P. E. and Walker, G. W., 1985. The flotation of chalcocite, bomite, chalcopyrite and pyrite in an electrochemical-flotation cell. 15th Inter. Miner. Process Congr., Cannes, France, 2 198 - 210... 

Watanabe, Y., Hagihara, H. Crystal structures of mercury ethylxanthate and mercury diethyldithiophosphate. Abstracts international union of crystallography, Kyoto, Japan 1972 (Acta Cryst. B28, 4 (1972)). 

Figure 17.1 Mode of action of sodium ethylxanthate as a froth flotation agent for sulfide minerals.

Methoxyphenylene diamine 12 was treated with potassium ethylxanthate to afford benzimidazole-thiol 13. The coupling of thiol 13 and chloromethyl-pyridine 11 was then... 

Two vanadium(iv) ethylxanthate complexes have been prepared 440 their e.p.r. parameters are practically identical with those of the corresponding diethyldithio-carbamate complexes and on this basis analogous structures were proposed, i.e. a dodecahedral eight-co-ordinate structure with four bidentate ethylxanthate ligands and a distorted tetrahedral structure with four unidentate ligands. Addition of phosphorus(iii) ligands (L) such as trialkylphosphites to solution of the ethyl xanthate... 

CdMe2 = dimethylcadmium, ZnEt2 = diethylzinc, TMS = trimethylsilyl, (BDMS)2Te = bis(tert-butyldimethylsilyl) telluride, TDPA = tetradecylphosphonic acid, ODPA = octadecylphosphonic acid, SA = stearic acid, LA = lauric acid, OA = oleic acid, MA = myristic acid, ac = acetate, my = myristate, st = stearate, hdx = hexadecylxanthate, ex = ethylxanthate, dx = decylxanthate, TOPO = trioctylphos-phine oxide, HDA = hexadecylamine, DA = dodecylamine, ODA = octadecylamine, TOP = trioctylphosphine, TBP = tributylphosphine, ODE = 1-octadecene, HH = hexadecyl hexadecanoate,... 

Bromo-5-methyl-l,6-naphthyridin-2-amine (53) with potassium O-ethylxanthate gave 8-methylthiazolo [4,5-b] L,6]naphthyridin-2(3//)-thione (54) (reactants, l-methylpyrrolidin-2-one, 165°C, 7h >95%) the 3-phenyl analog was made similarly.928... 

Diazotized 2-aminothiazole (4) with potassium ethylxanthate yields ethylthiazolyl-2-xanthate (5), which is then hydrolyzed to 2-mercaptothiazole (3) (8). Similarly, treatment of (4) by potassium thiocyanate gives the 2-thiocyano derivative (6), which is hydrolyzed to 2-mercaptothiazole (3) by 50% sulfuric acid (Scheme 2) (9). 

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