S,S'-dimethyl O,O'-2,2'-oxybis(ethane-2,1-diyl) dicarbonodithioate synthesis

Yield:198981-45-2 47%

Reaction Conditions:

Stage #1: diethylene glycolwith sodium hydroxide;tetrabutylammonium sulfate in water; for 0.166667 h;Alkaline aqueous solution;
Stage #2: carbon disulfide in water; for 0.333333 h;Alkaline aqueous solution;
Stage #3: methyl iodide in water at 20; for 4 h;Alkaline aqueous solution;

Steps:

195.i EXAMPLE 195: N-F2-L (TRIFLUOROMETHVL) OXYLETHVLL-N-{L (2, 4-DICHLORO) PHENVLLMETHS PIPERIDIN-4- amine L-Tartrate; (i)

Tetrabutylammonium sulfate (10.2 ml, 8.78 mmol) was added to diethyleneglycol (15G, 141 mmol), followed by 50% aqueous NAOH solution (285 ml,-12. 5 M). The reaction was stirred for 10 minutes, and then carbon disulfide (285 ml) was added dropwise over 20 minutes, followed by MeI (43.7g, 308 mmol). The reaction was stirred at ambient temperature for 4 hours before water (50 ml) was added. The layers were separated and the aqueous layer was extracted with dichloromethane. The combined organic extracts were washed with aqueous saturated sodium chloride, dried over MGS04, filtered, and concentrated IN VACUO. The crude material was purified on silica gel eluting with 70% dichloromethane/hexanes to yield (18.80g, 47%) of dithiocarbonic acid S- methyl ester 0- [2- (2-METHYLSULFANYLTHIOCARBOXYOXY-ETHOXY)-ETHYL] ester : 1H NMR (400 MHz, CDCl3) : 8= 4.6 (4H, m), 3.8 (4H, m), 2.5 (6H, s).

References:

WO2004/52858,2004,A2 Location in patent:Page 162-163