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List of Chemical Substances
Published in T.S.S. Dikshith, and Safety, 2016
Sulfur dioxide is a colorless gas. It is stable, and non-corrosive when dry to common materials except zinc. Sulfur dioxide is corrosive when wet and incompatible with strong reducing or oxidizing agents, moisture, zinc, and its alloys. Sulfur dioxide has a large number of industrial applications. For instance, sulfur dioxide is used in the manufacture of sodium sulfite, sulfuric acid, sulfuryl chloride, thionyl chloride, organic sulfonate, disinfectants, fumigants, industrial and edible proteins, etc. Sulfur dioxide is also used extensively as a bleaching agent, particularly in the bleaching of beet sugar, flour, straw, textiles, and wood pulp. Sulfur dioxide has industrial utility in the tanning of leather, in brewing and preserving. Sulfur dioxide is a colorless gas with a characteristic and strong suffocating odor.
3,4-Dichloro-1,2,5-thiadiazole: a commercially available electrophilic sulfur transfer agent and safe resource of ethanedinitrile
Published in Journal of Sulfur Chemistry, 2022
Hayedeh Gorjian, Nader Ghaffari Khaligh
Though various simple methods have been described for the synthesis of disulfide [22], only a few general approaches are available for the preparation of trisulfides, including (a) reactions of thiols with sulfur [23] or an electrophilic agent such as S(LG)2 (LG = good leaving group) (LG = Cl, imidazole, or phthalimido) at low temperature (−78 °C) in the presence of a base [24–28], (b) reactions of haloalkanes with the thio derivative of 1,3,4-oxadiazole [29], (c) reaction of organophosphorus thio derivatives with nucleophilic agents and organodisulfanyl anion with RS(LG) [30–32], and (d) the electrochemical method through the interaction of electro-generated sulfur cations with thiols [32,33] or various mediator redox systems and electrocatalysts [34,35]. The methods mentioned above are often non-selective, and a mixture of polysulfides is formed. Another method included the reaction of triphenylmethanesulfenyl chloride with acyclic disulfides [36]. However, triphenylmethanesulfenyl chloride is not stable at room temperature and decomposed in hot chloroform solution. Although some chemical companies sell these compounds, it is expensive (10 g/644 $ in Tokyo Chemical Industry (TCI)). Also, the preparation of this reagent required a toxic chemical, namely, sulfuryl chloride [37]. Other methods require unstable and toxic chemicals as sulfur transfer reagent and dual solvent-catalyst at low temperature (−78 °C) [24].
Selenium chlorides in the domino process of the regiospecific allyl chlorination of betulin and diacetylbetulin
Published in Journal of Sulfur Chemistry, 2020
I. V. Bodrikov, Yu. A. Kurskii, A. A. Chiyanov, A. Yu. Subbotin, A. S. Shavirin, N. V. Anderson
Selenium chloride was prepared by chlorinating metal selenium with sulfuryl chloride. To prepare a solution of SeCl2 to 0.45 g (5.7 mmol), finely dispersed Se was added to a solution of 0.77 g (5.7 mmol) of freshly distilled SO2Cl2 in 3 ml of chloroform. The mixture was rapidly stirred at room temperature until complete dissolution of selenium was observed. The freshly prepared solution of selenium chlorides was mixed with the solutions of 1a or 1b and the reaction mixture was stirred at room temperature. The precipitated red selenium was filtered off, the filtrate was washed with 10 ml of 3% sodium carbonate solution, and then with water (3 × 10 ml). The solvent was evaporated on a rotary evaporator and the precipitate was air dried.
Regioselective chlorination of phenols in the presence of tetrahydrothiopyran derivatives
Published in Journal of Sulfur Chemistry, 2019
Keith Smith, Des Williams, Gamal A. El-Hiti
Chemicals purchased from Aldrich and Lancaster Chemicals were mostly used as purchased. Sulfuryl chloride was distilled under an inert atmosphere at atmospheric pressure. Gas chromatography (GC) was carried out using a Shimadzu GC-2014 instrument with a capillary ZB Carbowax column (30 m, 0.32 mm ID) and temperature programed (40°C for 3 min, then ramped at 10°C/min to 220°C, then held for 8 min) with an injection temperature of 300°C and a detection temperature 250°C. To allow quantification, tetradecane was added as a standard. Commercial samples of expected phenol chlorination products were used to determine retention times and response factors for each product. 1H (400 MHz) and 13C NMR (100 MHz) spectra were recorded on a Bruker AV400 spectrometer. Chemical shifts δ are reported in parts per million (ppm) relative to TMS and coupling constants J in Hz have been rounded to the nearest integer. DEPT spectra were used to determine 13C multiplicities. Assignments of NMR signals are based on expected chemical shifts, integration values and coupling patterns and have not been rigorously confirmed. Low-resolution mass spectra were recorded on a Quattro II spectrometer at 70 eV. High-resolution mass spectra data were obtained on a MAT900 instrument.