Benzylic C(sp3)–H bond sulfonylation of 4-methylphenols with the insertion of sulfur dioxide under photocatalysis

2018 ◽  
Vol 54 (79) ◽  
pp. 11172-11175 ◽  
Author(s):  
Xinxing Gong ◽  
Jiahao Chen ◽  
Lifang Lai ◽  
Jiang Cheng ◽  
Jiangtao Sun ◽  
...  
Keyword(s):  
Sulfur Dioxide ◽  
Sodium Metabisulfite ◽  
Three Component Reaction

Sulfonylation of the benzylic C–H bond is developed through a three-component reaction of aryldiazonium tetrafluoroborates, 4-methylphenols and sodium metabisulfite (Na2S2O5). The inorganic sulfite of sodium metabisulfite is used as the SO2 surrogate.

Photoredox-catalyzed sulfonylation of difluoroenoxysilanes with the insertion of sulfur dioxide

2020 ◽  
Vol 56 (66) ◽  
pp. 9469-9472 ◽  
Author(s):  
Fu-Sheng He ◽  
Yanfang Yao ◽  
Wenlin Xie ◽  
Jie Wu
Keyword(s):  
Sulfur Dioxide ◽  
Sodium Metabisulfite ◽  
Silyl Ethers ◽  
Mild Conditions ◽  
Three Component Reaction ◽  
Enol Silyl Ethers

A photoredox-catalyzed three-component reaction of aryldiazonium tetrafluoroborates with sodium metabisulfite and 2,2-difluoro enol silyl ethers is described, providing α,α-difluoro-β-ketosulfones in moderate to good yields under mild conditions.

Generation of (E)-β-sulfonyl enamines from sulfur dioxide via a radical process

2021 ◽  
Vol 8 (8) ◽  
pp. 1789-1794
Author(s):  
Xiaodong Tu ◽  
Jiapian Huang ◽  
Wenlin Xie ◽  
Tonghao Zhu ◽  
Jie Wu
Keyword(s):  
Sulfur Dioxide ◽  
Radical Process ◽  
Three Component Reaction

An iron(ii)-catalyzed three-component reaction of O-acyl oximes, sulfur dioxide, and N-vinylacetamides is accomplished. Diverse (E)-β-sulfonyl enamines are obtained in moderate to good yields by using this protocol with excellent stereoselectivity and regioselectivity.

Synthesis of 6-(sulfonylmethyl)phenanthridines through a reaction of aryldiazonium tetrafluoroborates, sulfur dioxide, and vinyl azides

2018 ◽  
Vol 5 (17) ◽  
pp. 2555-2559 ◽  
Author(s):  
Xuefeng Wang ◽  
Yuewen Li ◽  
Guanyinsheng Qiu ◽  
Jie Wu
Keyword(s):  
Sulfur Dioxide ◽  
Three Component Reaction ◽  
Vinyl Azides

Synthesis of 6-(sulfonylmethyl)phenanthridines through a three-component reaction of aryldiazonium tetrafluoroborates, a sulfur dioxide surrogate of DABCO·(SO2)2, and vinyl azides under metal- and additive-free conditions is achieved.

A copper(ii)-catalyzed three-component reaction of aryldiazonium tetrafluoroborates, sulfur dioxide, with alkenes

2016 ◽  
Vol 3 (11) ◽  
pp. 1498-1502 ◽  
Author(s):  
Runyu Mao ◽  
Zheng Yuan ◽  
Rui Zhang ◽  
Yechun Ding ◽  
Xiaona Fan ◽  
...  
Keyword(s):  
Sulfur Dioxide ◽  
Three Component Reaction ◽  
Efficient Route

A three-component reaction of aryldiazonium tetrafluoroborates, sulfur dioxide, with alkenes catalyzed by copper(ii) bromide is developed, which provides an efficient route to (E)-alkenyl sulfones or allylic sulfones via the insertion of sulfur dioxide.

Adding Sulfur Dioxide (SO2)

2018 ◽  
Author(s):  
David R. Dalton
Keyword(s):  
Carbon Dioxide ◽  
Sulfur Dioxide ◽  
Safety Data ◽  
White Wine ◽  
Sodium Metabisulfite ◽  
Quality Grade ◽  
Grape Skins ◽  
Gaseous Sulfur ◽  
Carbon Dioxide Co2 ◽  
Liquefied Gas

The judicious use of sulfur dioxide (SO2) will inhibit the growth of microorganisms (e.g., bacteria) present on the grape skins as the berries come from the vineyard. Its early use presumes the vintner has decided that the adventitious wild yeasts which might be destroyed or inhibited by sulfur dioxide will not contribute to the vintage. It appears that Saccharomyces cerevisiae might be less susceptible to the action of sulfur dioxide than other yeasts that may be present. So, if the particular strain of S. cerevisiae used can cope, it may be able to function unimpeded. Regardless, sulfur dioxide might still be used because, in addition to suppression of deleterious microorganisms, it appears to reduce oxidation of particularly fragile white wine components. In industrial settings, both gaseous sulfur dioxide and sulfur dioxide as a liquefied gas (boiling point – 10 °C [14 °F]) are used. In either form it is a dangerous tool. It is dangerous first because it is toxic and second because an excess of it will ruin the wine. In many cases, because its value is recognized as beneficial, sulfur dioxide is replaced by addition of either sodium metabisulfite (Na2S2O5) or potassium metabisulfite (K2S2O5) with the latter generally preferred. Indeed, while it is best to look at the MSDS. (Manufacturer’s Safety Data Sheet) before use, the solubility of the two salts is the same and given as 450 grams/ liter (g/ L) at 68 °F (20 °C) and the pH on dissolution as between 3.5 and 4.5. The potassium (K) salt appears, at this writing, to be more readily available in food quality (as opposed to chemical quality) grade. So, with regard to sulfur dioxide (SO2), and as shown in Figure 17.1, its structure is much more similar to water and to ozone than it is to carbon dioxide (CO2); sulfur lies beneath oxygen (O2) in the periodic table (silicon, Si, lies beneath carbon). Nonetheless, sulfur dioxide (SO2) reacts with water much the same way that carbon dioxide (CO2) does.

C–H bond sulfonylation of anilines with the insertion of sulfur dioxide under metal-free conditions

2018 ◽  
Vol 54 (54) ◽  
pp. 7459-7462 ◽  
Author(s):  
Kaida Zhou ◽  
Jun Zhang ◽  
Lifang Lai ◽  
Jiang Cheng ◽  
Jiangtao Sun ◽  
...  
Keyword(s):  
Sulfur Dioxide ◽  
Metal Catalysts ◽  
Metal Free ◽  
Mild Conditions ◽  
Three Component Reaction

2-Sulfonylanilines are generated in moderate to good yields through a three-component reaction of anilines, DABCO·(SO2)2, and aryldiazonium tetrafluoroborates under mild conditions. No metal catalysts or additives are needed for this transformation.

A Copper-Catalyzed Three-Component Reaction of Triethoxysilanes, Sulfur Dioxide, and Hydrazines

2014 ◽  
Vol 16 (15) ◽  
pp. 4056-4058 ◽  
Author(s):  
Xianbo Wang ◽  
Lijun Xue ◽  
Zhiyong Wang
Keyword(s):  
Sulfur Dioxide ◽  
Three Component Reaction

scholarly journals Standardization of sodium metabisulfite solution concentrations and immersion time for farmed shrimp Litopenaeus vannamei

2015 ◽  
Vol 45 (3) ◽  
pp. 499-504 ◽  
Author(s):  
Luciana Trigueiro de Andrade ◽  
Nkarthe Guerra Araújo ◽  
Ana Paula Moraes Ventura ◽  
Andréa de Lucena Lira ◽  
Marciane Magnani ◽  
...  
Keyword(s):  
Sulfur Dioxide ◽  
Litopenaeus Vannamei ◽  
Immersion Time ◽  
Sodium Metabisulfite ◽  
Brazilian Legislation ◽  
So2 Concentration ◽  
All Treatment

Sodium metabisulfite is the main additive used in the prevention of melanosis in shrimp; however, it has currently been employed with great variation in concentration by producers. Thus, the aim of the present study was to determine the correlation between the concentration of the sodium metabisulfite solution and immersion time of the whole shrimp to obtain the concentration of sulfur dioxide (SO2) in the edible muscle of farmed shrimp (Litopenaeus vannamei) in accordance with the limit established by law. For this, solutions of sodium metabisulfite at different concentrations (1%, 2 %, 3 %, 4% and 5%) were prepared and samples of L. vannamei shrimp (100g) were immersed during 10, 20 or 30 minutes at temperature of 7°C. For all treatment assayed the concentration of SO2 was determined in the edible muscle of farmed shrimp (L. vannamei). The results show that for the conditions used in this study, the correlations were linear, with significant increase (P<0.05) in the SO2 concentration in the edible muscle of shrimps both increasing sodium metabisulfite concentration as increasing immersion times, suggesting the immersion of shrimps in a 3% solution for a time of 13 minutes in order to obtain SO2 concentration of 100ppm in its edible muscle in accordance with Brazilian legislation

FEEDING VALUE AND PRESERVATION OF HIGH MOISTURE GRAIN TREATED WITH SULFUR DIOXIDE

1988 ◽  
Vol 68 (4) ◽  
pp. 1209-1223 ◽  
Author(s):  
G. W. MATHISON ◽  
R. M. ELOFSON ◽  
L. P. MILLIGAN
Keyword(s):  
Sulfur Dioxide ◽  
Sodium Bicarbonate ◽  
Dry Matter ◽  
Good Condition ◽  
Sodium Metabisulfite ◽  
Feed Conversion ◽  
High Moisture ◽  
Ambient Temperatures ◽  
Single Location ◽  
Feeding Value

Five experiments were conducted to evaluate the effectiveness of sulfur dioxide as a moist grain preservative. In exp. 1 barley containing 30% moisture was treated with 0, 0.25, 0.5, 0.75 and 1.0% (wt/wt) sulfur dioxide and stored in 300-kg lots in wooden boxes from May to August. Grains treated with the two highest levels of chemical were well preserved. Sulfur dioxide treatment did not influence (P > 0.05) apparent digestibilities of dry matter (DM) or energy. In exp. 2, approximately 26 t of barley (22% moisture) were preserved with 1% sulfur dioxide. This material was in good condition when fed after 6 mo of storage; however, grain thiamin levels were below detectable limits and the sulfur content of the grain was increased from 0.27 to 0.68% (DM basis). Daily gains and gain: feed DM ratios were similar (P > 0.05) for 23 steers given dry barley and 24 steers given sulfur dioxide-treated barley during a 104-d feeding period when the grains were included in diets containing 90% concentrate with or without added thiamin. Dry matter intake of steers fed sulfur dioxide-treated grain tended (P < 0.10) to be reduced in the first 28 d of the trial (6.9 vs. 7.3 kg d−1) and final carcass backfat depths were reduced from 1.17 to 0.92 cm (P < 0.05) when treated grain was fed. In exp. 3 a barley/oat grain mixture (21% moisture) was treated with 1% sulfur dioxide in September 1983 and stored in a 22-t bin. The grain was well preserved when removed from the bin in November 1983. Sulfur dioxide treated-grain or addition of sodium bicarbonate to the diet had no influence (P > 0.05) on rate of gain, feed conversion or carcass weight when compared to dry grain when 16 heifers per treatment were fed 0.75 kg hay plus concentrate ad libitum. Carcass backfat depths were reduced (P < 0.05) from 1.16 to 0.92 cm when sulfur dioxide-treated grain was fed but were increased to 1.47 cm when sodium bicarbonate was added to the diet containing treated grain. In exp. 4 sodium metabisulfite preserved damp grain from October to January. In the last experiment the movement of sulfur dioxide through grain was examined. It was found that the chemical was ineffective when added at a single location at the bottom of a bin. It was concluded that sulfur dioxide and sodium metabisulfite are useful preservatives for high-moisture grain in small bins when the moisture content is below 30% and the ambient temperatures are cool. Key words: Sulfur dioxide, sodium metabisulfite, high-moisture grain, preservatives, cattle

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