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Cyclic trithiocarbonates, synthesis

Abstract Anhydro sugars have proved to be versatile chiral synthons for the synthesis of chiral heterocycles including pyradazines, oxazines, triazines, chiral morpholines, tetrahydroquinoxalines, benzodioxins, oxazolidinones, episulfides, thiazolines, and cyclic trithiocarbonates. Selected examples are described in this chapter. [Pg.325]

Synthesis.—In the course of their investigations in the field of simple trithiocarbonates, Gattow and his co-workers have prepared the cyclic trithiocarbonates (284) and (285) by reactions involving the action of methylene iodide on potassium trithiocarbonate, and the treatment of hydrogen trithiocarbonate with dimeric thiophosgene, respectively. The... [Pg.258]

Titanium complexes have been shown to be active for the synthesis of cyclic carbonates or either di- or trithiocarbonates from epoxides and either carbon dioxide or carbon disulfide (Scheme 5.6). Titanium-catalysed synthesis of cyclic carbonates has been recently reviewed by North and coworkers. Titanium-salen complexes find application as catalysts, in combination with tetrabutylammonium bromide or tributylamine, for the synthesis of di- or trithiocarbonates from epoxides and carbon disulfide. It is worth highlighting that the catalyst loading can be reduced to 0.5 mol%, although 1 mol% of catalyst was required in order to achieve quantitative yields. The catalyst system showed a preference for dithiocarbonate formation for most of the epoxides studied. [Pg.108]

Several examples of the applicability of carbon disulphide in the synthesis of cyclic as well as open-chain thiono- and trithio-carbonates have appeared. Thus dithallous glycolates reacted with excess of carbon disulphide to form ethylenethionocarbonates together with spiro-orthocarbonates, and the formation of tetramethyl orthocarbonate in the reaction between thallous ethoxide and carbon disulphide evidently proceeded via intermediate diethyl thionocarbonate. Klingsberg obtained 5,6-dimethyl-l,3-dithiole-2-thione by the reaction of 4,5-dimethylbenzene-1,2-dithiol with carbon disulphide. The thiirans (390 R = Me, R = R = H) reacted with carbon disulphide in basic media to yield 4-methylthio-l,3-di-thiole-2-thiones (429). Successive treatment of 2,2-diphenylethylene-sulphonamide with carbon disulphide and alkyl halides in the presence of a base afforded the unsaturated trithiocarbonate (430), and the symmetrical trithiocarbonate (431) was formed by the simultaneous action of sodium sulphide and carbon disulphide on the oxathiolan derivative (432). ... [Pg.296]


See other pages where Cyclic trithiocarbonates, synthesis is mentioned: [Pg.326]    [Pg.253]    [Pg.110]    [Pg.362]   
See also in sourсe #XX -- [ Pg.132 ]




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