3775-21-1Relevant articles and documents
Solvent-Free Condensation Reactions to Synthesize Five-Membered Heterocycles Containing the Sulfamide Fragment
Arroyo, Nelson Rodríguez,Rozas, María F.,Vázquez, Patricia,Romanelli, Gustavo P.,Mirífico, María V.
, p. 1344 - 1352 (2016/05/02)
We report a study of the solvent-free condensation reaction of 1,2-dicarbonyl compounds with sulfamide catalyzed by a Keggin-type acid (H3PMo12O40·nH2O, MPA) to obtain 3,4-disubstituted 1,2,5-thiadiazole 1,1-dioxide derivatives. Some reactions were also performed in solution or using nano-sized silica-supported MPA catalyst in order to compare the results under different experimental conditions. Effects of the temperature used for the thermal pretreatment of the catalyst, the reaction temperature, the molar ratios sulfamide/1,2-dicarbonyl compound and MPA/1,2-dicarbonyl compound, and alternative experimental procedures on the yield of the reaction product were investigated. Under suitable experimental conditions eight compounds were obtained in good yields. The catalyst was recycled and reused, but with some loss of its catalytic activity. The presented synthetic method is a simple, clean, and environmentally friendly alternative for synthesizing different 1,2,5-thiadiazole 1,1-dioxide derivatives.
Electrochemical and spectroscopic study of the addition of several nucleophiles to 1,2,5-thiadiazole 1,1-dioxide derivatives
Aimone, Silvia Lucia,Caram, Jose Alberto,Mirifico, Maria Virginia,Vasini, Enrique Julio
, p. 272 - 282 (2007/10/03)
The nucleophilic addition reactions of several alcohols and 1-propanethiol to a C=N double bond of 3,4-disubstituted derivatives of 1,2,5-thiadiazole 1,1-dioxide were studied in acetonitrile solution. The substrates used were 3,4-diphenyl (1a), 3-methyl-4-phenyl (1b), phenanthro[9,10-c] (1c) and acenaphtho[1,2-c]-1,2,5-thiadiazole 1,1-dioxide (1d), 3,4-diphenyl-1,2,5-thiadiazoline 1,1-dioxide (2a) and 4-ethoxy-5-methyl-3,4-diphenyl-1,2,5-thiadiazoline 1,1-dioxide (2b). Spectroscopically (UV-VIS) and electrochemically (cyclic voltammetry) measured equilibrium constants at 25.0°C are presented and discussed for the reaction of 1a and 1b with alcohols (methanol, n-propanol, n-butanol, isobutanol, 2-propanol, sec-butanol, tert-butanol, ethylene glycol, allyl alcohol and 2-phenylethanol). A reaction of 1-propanethiol with 1c was observed, but the alcohols did not react with 1c, 1d or the thiadiazolines (2a, 2b). The effect of the solvent on the equilibrium constant of the 1a-ethanol system was measured using, besides acetonitrile, propylene carbonate, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and tert-butanol. The results were correlated with an empirical H-bond acceptor solvent parameter. Previously unreported spectroscopic (UV-VIS, IR, 1H and 13C NMR) data for some of the compounds studied are also provided. Copyright
