Carbon tetrachloride/thiourea

Symmetrical dialkyl and diaryl thioureas have been prepared in generally good yield (60-90%) from the reaction of the amine with thiophosgene, formed in situ from the catalysed reaction of carbon tetrachloride with sodium sulphide [5], Reaction with diamines yields cyclic ureas. 

The desulfurization of thioureas can also be effected with triphenylphosphine in the presence of triethylamine and carbon tetrachloride. In this manner carbodiimides 19 are obtained in over 90 % yield." ... 

Carbodumide synthesis. 1,3-Disubstituted ureas or thioureas react with tri-phenylphosphinc, carbon tetrachloride, and Iriethylamine in methylene chloride at 40° to give carbodiimides in yields of 85-92%. 

Eight methyl A -(l//-benzimidazol-2-yl)carbamates 78 with various 5-substituents have been labelled with at carbon-2, and at the carbonyl and methoxy carbons according to the synthetic scheme of equation 25 using commercially available C-enriched (91-92 atom%) carbon tetrachloride, methanol and thiourea. The three labelled positions indicated with asterisks are at or near the site involved in binding to tubulin (which performs a variety of vital functions in the cell). A correlation has been found between anthelmintic potency of the benzimidazole carbamate group of anthelmintic drugs widely used to control nematode parasites in sheep and their ability to bind tubulin. 

The use of carbonyl chloride in the conversion of thioureas to chloro-formamidines offers the advantage of gaseous by-product. Phosphorus pentachloride can be used equally well, but complete separation from the liquid trichlorophosphorus sulfide is sometimes more difficult to accomplish. In one instance, chlorine has been used to convert a pseudothiourea derivative to the corresponding chloroformamidine hydrochloride. Thus, addition of chlorine to a solution of the pseudothiourea derivative XIII in carbon tetrachloride afforded a quantitative yield of trimethylchloro-formamidine hydrochloride (XIV) C ). 

The Hugerschoff reaction is a classical method to convert arylthioureas into aminobenzothiazoles under oxidative conditions. It was discovered by Hugerschoff in the early 1900s, who found that an arylthiourea can be cyclized with liquid bromine in chloroform to form a 2-aminobenzothiazole. Solvents such as carbon tetrachloride and carbon disulfide can also be used. This transformation is aided by thiophilic bromine or its equivalent and requires an intramolecular aromatic elecb ophilic substitution reaction of the aryl ring to the thiocarbonyl group of thiourea. Attempts have been made to avoid the use of bromine due to the handling concerns it poses. For example, Jordan and coworkers have used benzyltrimethylammonium tribromide. ... 

Thiourea forms channel-type inclusion compounds with globular molecules.This is partly because the space group E3c lacks a screw axis that the space group of the urea inclusion compounds P6i22 possesses. The larger diameter of the channel than in the urea compounds accommodates cyclohexane and monosubstituted cyclohexane as well as carbon tetrachloride and hexachloro-ethane in the channel. With these more or less spherical molecules as the guest species, thiourea inclusion compounds are rich in their polymorphism, most undergoing two or more phase transitions below room temperature. 

Sekii, M. Matsuo, T. Suga, H. Calorimetric study of phase transitions in the thiourea carbon tetrachloride inclusion compound. J. Inch Phenom. Mol. Recognit. 1990, 9, 243. 

The inclusion properties of urea were discovered by Ben-gen in 1940 and this tubulate host has since become one of the most studied. Thiourea and selenourea form related, but slightly different, clathrate structures. Figure 1 illustrates the structure of the (thiourea)3 -(carbon tetrachloride) compound. Many 1,3-diarylurea derivatives also include guest molecules, but these produce hydrogen-bonded complexes with acceptor guest species, rather than clathrates. " ... 

Figure 1 A cross-sectional slice across four tubes of the (thiourea)3-(carbon tetrachloride) clathrate structure. Host color code C, bright green S, yellow N, dark blue and H, light blue. Guest C, purple and Cl, pale green. Only one orientation of the disordered guest is shown. ...

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