Thiocarbamic esters

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... 

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. 

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. 

An alternative method for the synthesis of different dextran conjugates with fluorescent dyes is the reaction of a water-soluble amino dextran with the succinimidyl ester of the corresponding dye [360]. The amide linkage is more stable than the corresponding thiocarbamate formed with isothiocyanates. This method is displayed schematically in Fig. 54 for the preparation of 5- (and 6-) carboxynaphthofluorescein-labelled dextran from amino dextran (Fig. 47, [361,362]). 

It has been reported <1998CC2315> that a similar [2+2] intramolecular cyclization of (2-cyclohex-l-enyl-2-methyl-propionyl)phenyl-thiocarbamic acid O-methyl ester leads to the formation of tricyclic thietane in 85% yield (Table 2). 

Chemical Name carbamic acid, dipropylthio-, 5-ethyl ester 5-ethyldipropyl(thiocarbamate) 5-ethyldipropylcarbamo-thioate... 

Metribuzin heterocyclic nitrogen, triazine Metsulfovax heterocyclic nitrogen thiazole, amide Metsulfuron-methyl sulfonyl urea Mevinphos phosphoro organic, phosphate ester Mexacarbate carbamate Mirex halogenated hydrocarbon Molinate thiocarbamate Monalide amide... 

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