3553-61-5Relevant academic research and scientific papers
1,2,4-Dithiazole-5-ones and 5-thiones as efficient sulfurizing agents of phosphorus(iii) compounds - A kinetic comparative study
Ponomarov, Oleksandr,Laws, Andrew P.,Hanusek, Ji?í
supporting information, p. 8868 - 8876 (2013/01/15)
The sulfurization efficiency of 25 3-substituted-1,2,4-dithiazole-5-ones and 5-thiones towards triphenyl phosphite in acetonitrile, DCM, THF and toluene at 25 °C was evaluated. All the 1,2,4-dithiazoles are much better sulfurizing reagents than commercially available agents (PADS, TETD, Beaucage's reagent). The most efficient sulfurizing agents in all solvents are 3-phenoxy (4), 3-phenylthio (5) and 3-ethoxy-1,2,4-dithiazole-5-one (1) whose reactivity is at least two orders of magnitude higher than that of other 1,2,4-dithiazoles. Contrary to a previous report, the sulfurization with 1 does not yield carbonylsulfide and ethyl cyanate as the additional reaction products but unstable ethoxythiocarbonyl isocyanate which has been trapped with 4-methoxyaniline. Similar trapping experiments have proven that the site of attack is at the sulfur adjacent to the CO group for compounds 4 and 5. The reaction pathway involves rate-limiting initial nucleophilic attack of the phosphorus at sulfur followed by decomposition of the phosphonium intermediate to the corresponding phosphorothioate and isocyanate/isothiocyanate species. The existence of the phosphonium intermediate during sulfurization of triphenyl phosphine with 3-phenyl-1,2,4-dithiazole-5-thione (7a) was proven using kinetic studies. From the Hammett and Bronsted correlations and from other kinetic measurements it was concluded that the transition-state structure is almost apolar for the most reactive 1,2,4-dithiazoles whereas a polar structure resembling a zwitter-ionic intermediate may be more appropriate for the least reactive 1,2,4-dithiazoles. The extent of P-S bond formation and S-S bond cleavage is very similar in all reaction series but it gradually decreases with the reactivity of the 1,2,4-dithiazole derivatives.
Facile synthesis of 2-azaazulenes from thiobenzoyl isocyanates using trimethylsilyldiazomethane
Morita, Mikio,Hari, Yoshiyuki,Iguchi, Tomoe,Aoyama, Toyohiko
, p. 1753 - 1758 (2008/09/17)
The reaction of trimethylsilyldiazomethane with thiobenzoyl isocyanates, in situ generated from thiazole-4,5-diones, yielded diazoketones, which were converted into 2-azaazulenes by the intramolecular Buchner reaction.
Thioacyl Isocyanates, XII. Preparation and Comparison of Aliphatic, Aromatic, and Heteroaromatic Compounds
Goerdeler, Joachim,Nandi, Kumaresh
, p. 549 - 563 (2007/10/02)
Many 1,2,4-dithiazol-3-ones (2), especially with aliphatic and heterocyclic substituents, and some thiazoline-4,5-diones (3) were synthesized from thioamides (1).Extrusion of sulfur or carbon monoxide, respectively, afforded the thioacyl isocyanates 5.Rea
Thioacyl Isocyanates, XV. Reaction with Nucleophilic C-Compounds
Goerdeler, Joachim,Tiedt, Marie-Louise,Nandi, Kumaresh
, p. 2713 - 2722 (2007/10/02)
Reaction of thioacyl isocyanates with sodium ethylmalonate and related compounds affords 1, existing as amides or tautomers; they are suitable as starting material for the synthesis of 2, 3, 4. - Thiobenzoyl isocyanate reacts with nucleophilic alkenes and
