N-Phenyltriazolinedione as an efficient, selective, and reusable reagent for the oxidation of thiols to disulfides

Green and Metal-free Catalytic Oxidation of Urazoles into Triazolinediones by Guanidinium Nitrate and Catalytic Amounts of Silica Sulfuric Acid

“…Chemicals were purchased from Fluka, Merck and Aldrich chemical companies. The oxidation products were characterized by comparison of their spectral (IR, 1 H NMR, and 13 C NMR) and physical data with authentic samples. [24][25][26] Oxidation of 4-(4-methoxyphenyl)-urazole to 4-(4-methoxyphenyl)-1,2,4-triazoline-3,5-dione with guanidinium nitrate and silica sulfuric acid.…”

Glycerol as a recyclable solvent in a microwave-assisted synthesis of disulfides

“…These aspects are responsible for the continuous interest in development of new, selective and efficient protocols for the preparation of disulfides (20Á22, 24Á34). Recently reported procedures involve the use of stoichiometric amount of anhydrous potassium phosphate (24), potassium permanganate (25), molecular bromine supported on silica gel (26), N-phenyltriazolinedione (27), VO(acac) 2 (28), trichloroisocyanuric acid (29), nitric acid (30), 1,3-dibromo-5,5-dimethylhydantoin (31), basic alumina (32), CsF-Celite (33), and montmorillonite K10 (34).…”

“…These methods involve the use of N-phenyltriazolinedione (27) Despite several advantages, the solvent-free methods are restricted to systems where at least one of the reagents is liquid at room temperature, whereas the uses of ionic liquids, especially imidazolium systems with PF 6 and BF 4 anions, have some drawbacks, such as the high cost and liberation of hazardous HF *Corresponding author. Email: lenardao@ufpel.edu.br (E.J.…”

Versatile and Efficient Conversion of Thiols into Disulfides by Poly(4-vinylpyridinium tribromide) as Reusable Oxidizing Polymer

“…[1][2][3][4] The classical procedures for this type of reaction use reagents such as silica-PCl 5 /NaNO 2 , 2 NaBrO 3 /NaBr, 3 1-chlorobenzotriazole, 5 rosolic acid, 6 polyvinylpyrrolidone (PVP)-capped silver nanoparticles, 7 H2O2/NaI, 8 CeCl3․7H2O/I2, 9 molybdate sulfuric acid/NaNO 2 10 silica sulfuric acid/NaNO 2 11 ethylenebis(N-methylimidazolium) chlorochromate, 12 wet NaIO 4 13 Nphenyltriazolinedione, 14 monochloro poly(styrenehydantoin), 15 and urea-hydrogen peroxide (UHP)/maleic anhydride. 16 There are a variety of reports on the functionalization of organic compounds with molecular bromine.…”