Trithiocarbonates, cyclic

Segmented copolymers can also be prepared by polymerization in the presence of appropriate cyclic trithiocarbonates as RAFF agents.661... 

Cyclic trithiocarbonates are conveniently prepared by the phase-transfer catalysed reaction of 1,2- and 1,3-dichloro- and dibromoalkanes with sodium trithiocarbonate [47]. Diodoalkanes produce alkenes. 

Benzo[7]thiete 41 reacts in the ortho-qumoiA isomer 41 with cyclic trithiocarbonates such as l,3-dithiolane-2-thione, (ethylene trithiocarbonate), l,3-dithiole-2-thiones, and adamantanethione <1997LA1603>. In boiling toluene, 1,3 dithiolane and dithiole derivatives formed the spiro compound 42 and 43 in good yield. The related l,3-dithiole-2-thiones reacted chemoselectively at the C=S double bond. The use of adamantanethione yielded the polycyclic adduct 44 in a smooth and quantitative reaction (Scheme 3). 

In order to clarify the mechanism, the reaction of carbon disulphide with mercury bis(n-butanethiolate) was studied. On the basis of results obtained, it was suggested that this reaction involved the formation of a coordination complex, followed by the formation of active species containing the Hg-SC(S) bond. Moreover, the cyclic trithiocarbonate, ethylene trithiocarbonate, found to be present in trace amounts in copolymerisation products, was excluded as a possible intermediate for the copolymer formation, since it did not undergo any polymerisation under the given conditions [249],... 

The reaction of 1,2-dichlorodiethyl ether with potassium trithiocarbonate leads to the formation of the cyclic thione (318) which on treatment with p-toluenesulfonic acid gives... 

The author [3] developed a method for preparing cyclic trithiocarbonates, (II), using epoxides in the ionic solvent l-butyI-3-methyIimidazoIium... 

Several cases have been reported in which the reactivity of the C-C douhle hond towards nucleophilic attack is further enhanced by an external electrophile. An example of an exo-trig cyclization induced by mercuration is shown in the case of the unsaturated acid rac-1 which was converted to the cyclic acetals (otR,2S)-2 and (y.S.2S)-2 employing mercury(ii) acetate in methanol followed by subsequent demercuration40. In the latter step, sodium trithiocarbonate afforded the highest selectivity in terms of retention of configuration (cf. Section 4.7.1.1.1.1.2.). 

The cyclic ylide 592 reacted with the trithiocarbonate 588 to give the 2,2,4,4-tetrasubstituted-l,3-dithiolane 593 in a moderate (42%) yield. The regioselectivity of this cycloaddition was opposite to that observed for the ylide 589 (Scheme 84) <2003CEJ2256>. 

The preparation of trithiocarbonates from aliphatic and cyclic oxiranes can be achieved with sodium 0-ethylxanthate (Eq. 219). ° ... 

Cyclic trithiocarbonates undergo oxidative addition with the complex [Pt(PPhj)4], resulting, by the cleavage of a C—S bond, in the unusual heterometallacyclic compounds with structure 18 ( = 2, 3) (43). 

Cyclic trithiocarbonate complexes of type le [L = CO, P(OMe)j] (Table I) undergo ring opening on deprotonation (100). Alkylation of the formed anion affords a new type ofcarbene complex, 106, as well as complex 107,... 

These dimeric cations are reactive species and frequently, under preparative oxidation conditions, different products are obtained. Cyclic trithiocarbonates, for example, in moist acetonitrile can eliminate sulfur and react with water, yielding the corresponding carbonyl compound [222] ... 

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

An example of the simultaneous anti-powdery mildew and acaricidal action is the biological effect of 6-methyl-2,3-quinoxalinedithiol cyclic carbonate (oxythio-quinox, 30) and of the related 2,3-quinoxalinediyl cyclic trithiocarbonate (thioquinox, 31), introduced originally as fungicides against powdery mildew and discussed already under the heading fungicides. These compounds were developed by research workers of the Bayer Co. in the course of their study of the acylated derivatives of 2,3-dimercaptoquinoxaline (Sasse et ai, 1958 19 Basse, 1960). 

As an example of a conjugated it electron system involving the thiocarbonyl group we consider the cyclic trithiocarbonate l,3-dithiole-2-thione (iS). 38 and its selenium analogues 39-43 comprise an ideal series for the study of the valeqce... 

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. 

Epoxy triflates (e.g., 1, 2, 127-129) are also useful synthons for a simple and efficient route to cyclic trithiocarbonates (e.g., 126-134) [95]. Formation of these trithiocarbonates involves the addition of a red aqueous solution of Na2CS3 [96] to a stirred solution of epoxytriflate. The nucleophilic displace-... 

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. 

Dibromobutyne was used in the preparation of cyclic trithiocarbonates with a propadiene side-chain. From potassium trithiocarbonate, a double substitution occurs in the presence of 18-c-6. 59 Sonication speeds up the reaction by a factor of 10. Without sonication, only polymers are formed. 

---