Thiocarbamates Thiocarbamic esters

The condensation of /V-cyanoamidines with thiocarbamate esters provides routes to 1,3,5-triazine thioethers (Scheme 55), and dimethylamino-1,3,5-triazines (Scheme 56). Melamine (520) can be prepared by fusing dicyanamide (519) (40MI22000). 

The condensation of JV-cyanoamidines with thiocarbamate esters (107) provides routes to 1,3,5-triazine thioethers (108 Scheme 62), and dimethylamino-l,3,5-triazines (109 Scheme 63). In addition, novel chloromethylenimino salts (e.g. 110 R6 = OPh) may be prepared in situ (Scheme 63). Typical examples are shown in Table 11. 

Dimethylaminoazirines (227) react similarly with isocyanates or isothiocyanates to form imid-azolinones or the corresponding thiones <88JOC5298>. With carbamate or thiocarbamate esters (227) gives imidazolin-2-ones <82H(19)2079> or thiohydantoins (Scheme 159) <90HCA594>. 

Mercaptoacetic acid adds very readily to nitriles and, according to Condo and his co-workers85 can be used for direct identification of nitriles it gives the adducts in 80-90% yield when a solution of the nitrile and mercaptoacetic acid in anhydrous ether is saturated at 0° with dry hydrogen chloride. Hydrogen sulfide and thiols add to cyanic esters, giving respectively thiocarbamic esters and (alkylthio)formimidic esters homogeneously, under mild conditions, and in almost quantitative yield 86... 

O-(2,4-Dimethylphenyl) thiocarbamate 87 2,4-Dimethylphenyl cyanate (7.35 g, 50 mmoles) is added to a solution of sodium thiosulfate pentahydrate (12.4 g, 50 mmoles) in water (30 ml) and ethanol (20 ml) then 1 % sulfuric acid (25 mmoles) is dropped in. After a short while the thiocarbamic ester, m.p. 139-140° 85 g, 93.5%), crystallizes. 

Aromatic sulphonyl chlorides may be prepared, in excellent yields, by the oxidation of a thiocarbamic ester (a masked thiol), after initial Newman-Kwart rearrangement597, as shown in equation 151. The latter is readily prepared from phenols. 

Thioiminocarbonic acid esters Thiolcarbamic -Thiocarbamate esters 40 Thionocarbamic... 

Dolfen D, Schottler K, Valiahdi S-M et al (2008) Synthesis, structures and in vitro cytotoxicity of some platinum(II) complexes containing thiocarbamate esters. J Inorg Biochem 102 2067-2071... 

Reaction wifli Salts and Esters of Thiocarbamic Acid 2-Hydroxythiazoles and Derivatives... 

Hydroxythiazoles give 2-chIorothiazole derivatives almost quantitatively upon treatment with phosphorus oxychloride (221, 229, 428). This constitutes a convenient synthesis method for these compounds when the conversion of 2-aminothiazoles to 2-chlorothiazole derivatives fails. Esters of thiocarbamic acid or thiourethanes also react with a-halocarbonyl compounds to give the corresponding 2-alkoxythiazoles (50, 68, 209, 272). 

The Pd-catalyzed allylic alkylation of sulfinate ions, thiols, and thiocarboxylate ions with racemic cyclic and acyclic allylic esters in the presence of bisphosphane BPA generally provides for an efficient asymmetric synthesis of allylic sulfones, sulfides, and thioesters. The Pd-catalyzed rearrangements of allylic sulfinates and allylic O-thiocarbamates, both of which proceed very efficiently in the presence of BPA, are attractive alternative ways to the asymmetric synthesis of allylic sulfones and allyUc thioesters also starting from the corresponding racemic alcohols. 

Research Focus Preparation of IV-substituted imide dialkyl-thiocarbamic acid esters as high-activity polymerization initiators. 

TABLE 2. Pendulum Hardness and Cross-Hatch Testing Results for Polymers Prepared Using Selected Dialkyl-Thiocarbamic Acid Esters... 

Radical deoxygenation of sugars can be realized with suitable alcohol derivatives such as esters (acetates, pivaloates), sulfur compounds (xanthates, thiocarbamates, tri-fluoromethylsulfonates) according to the general Scheme 41. 

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