The cheap and easily available sodium dithionite and thiourea dioxide have been used as the source of sulfonyl group in the synthesis of sulfones and sulfonamides recently.Compared with other methods for the sulfonyla...The cheap and easily available sodium dithionite and thiourea dioxide have been used as the source of sulfonyl group in the synthesis of sulfones and sulfonamides recently.Compared with other methods for the sulfonylation reactions,the strategies using sodium dithionite or thiourea dioxide provide an alternative and complementary route to diverse sulfonyl compounds.During the reaction process,sulfur dioxide anion radical is the key intermediate,which is usually generated from a single electron transfer under suitable conditions.The advantages using sodium dithionite or thiourea dioxide in the sulfonylation reactions include mild conditions and broad substrate scope with excellent functional group compatibility.Further applications by using sodium dithionite and thiourea dioxide in organic transformations will be anticipated.展开更多
The sulfinatodehalogenation reaction of α,α-difluorobenzyl handes, ArCF_2X (Ar = CAFS, C_6H_5; X = Br, I ), with sodium dithionite took place readily in aqueous acetonitrile under mild conditions. giving the corresp...The sulfinatodehalogenation reaction of α,α-difluorobenzyl handes, ArCF_2X (Ar = CAFS, C_6H_5; X = Br, I ), with sodium dithionite took place readily in aqueous acetonitrile under mild conditions. giving the corresponding sodium sulfinate. The 1: 1 adducts were obtained when alkenes were added to the reaction system in some cases.展开更多
A new fluorinated anionic surfactant Cl（CF2）6O（CF2）2SO3N（C2H5）4 was prepared and characterized. The application of the fluorosurfactant allowed the fluoroalkylation to occur in the water without adding organic s...A new fluorinated anionic surfactant Cl（CF2）6O（CF2）2SO3N（C2H5）4 was prepared and characterized. The application of the fluorosurfactant allowed the fluoroalkylation to occur in the water without adding organic solvent. The addition of perfluoroalkyl iodides with olefins and alkynes under the initiation of Na2S2O4 in water in the presence of the fluorosurfactant gave the corresponding adducts in good to excellent yields. The fluorosurfactant was suitable for a radical addition process.展开更多
This study investigates the removal of arsenite（As（III）） from water using dithionite activated by UV light. This work evaluated the removal kinetics of As（III） under UV light irradiation as affected by dithionit...This study investigates the removal of arsenite（As（III）） from water using dithionite activated by UV light. This work evaluated the removal kinetics of As（III） under UV light irradiation as affected by dithionite dose and light intensity, and characterized the nature of the precipitated solids using XPS and SEM-EDS. Photolysis of dithionite was observed by measuring dithionite concentration using UV absorbance at 315 nm. This study also investigated the effect of UV light path length on soluble As concentrations to understand resolubilization mechanisms. Total soluble As concentrations were observed to decrease with reaction time due to reduction of arsenite to form solids having a yellow-orange color.The removal mechanism was found to be reductive precipitation that formed solids of elemental arsenic or arsenic sulfide. However, these solids were observed to resolubilize at later times after dithionite had been consumed. Resolubilization of As was prevented and additional As removal was obtained by frequent dosing of dithionite throughout the experiment. As（III） removal is attributed to photolysis of dithionite by UV light and production of reactive radicals that reduce As（III） and convert it to solid forms.展开更多
A novel synthesis of polyfluoroalkyl substituted -butyrolactones from the reaction of polyfluoroalkyl iodides with 4-pentenoic acid initiated with sodium dithionite was realized in good yields.
Bleaching of the kaolin ore from Shaziling Kaolin Mine in Jiangxi Province of China was studied with the aim of enhancing the quality and value of the ore to meet the requirements from the ceramics manufacturers. Fact...Bleaching of the kaolin ore from Shaziling Kaolin Mine in Jiangxi Province of China was studied with the aim of enhancing the quality and value of the ore to meet the requirements from the ceramics manufacturers. Factors affecting the reductive bleaching of kaolin ore with sodium dithionite as the bleaching agent were studied and optimized to increase the whiteness of the kaolin ore from 38. 5% to about 65%. However, it was found that in the conventional bleaching process, a washing step to remove the ferrous ions from the bleached kaolin suspension was indispensable, which made the process complicated and restricted the capacity of the production. In addition, the whiteness of the bleached kaolin products was unstable. To solve the above problems, a new technique with the application of chelating agents in the bleaching process was developed to remove ferrous ions and get rid of the washing step. The bleaching process of kaolin was simplified. The whiteness of the bleached kaolin products was stabilized as well as increased to about 70%. The mechanism of the bleaching process and the action of the chelating agents were discussed.展开更多
Reduced species （HSO2^-, SO2^·-） promoted one-pot synthesis of phenyl alkyl selenides has been developed. This synthetic method was achieved by reactions of diphenyl diselenide with alkyl halides at room temper...Reduced species （HSO2^-, SO2^·-） promoted one-pot synthesis of phenyl alkyl selenides has been developed. This synthetic method was achieved by reactions of diphenyl diselenide with alkyl halides at room temperature. It is noteworthy that the reactions were operated under mild reaction conditions, required short time, and got good resuits. A single electron transfer reaction mechanism was proposed for the reaction.展开更多
基金Financial support from the National Natural Science Foundation of China(Nos.21871053 and 21532001)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(No.2019R01005)is gratefully acknowledged。
文摘The cheap and easily available sodium dithionite and thiourea dioxide have been used as the source of sulfonyl group in the synthesis of sulfones and sulfonamides recently.Compared with other methods for the sulfonylation reactions,the strategies using sodium dithionite or thiourea dioxide provide an alternative and complementary route to diverse sulfonyl compounds.During the reaction process,sulfur dioxide anion radical is the key intermediate,which is usually generated from a single electron transfer under suitable conditions.The advantages using sodium dithionite or thiourea dioxide in the sulfonylation reactions include mild conditions and broad substrate scope with excellent functional group compatibility.Further applications by using sodium dithionite and thiourea dioxide in organic transformations will be anticipated.
基金the National Natural Science Foundation of China ! 29772041.29632003
文摘The sulfinatodehalogenation reaction of α,α-difluorobenzyl handes, ArCF_2X (Ar = CAFS, C_6H_5; X = Br, I ), with sodium dithionite took place readily in aqueous acetonitrile under mild conditions. giving the corresponding sodium sulfinate. The 1: 1 adducts were obtained when alkenes were added to the reaction system in some cases.
基金Acknowledgments We are grateful for the financial support from the 973 Program of China （No. 2012CB821600）, the National Natural Science Foundation of China （Nos. 21172241, 21032006） and the Science and Technology Commission of Shanghai Municipality （No. 11ZR1445700）.
文摘A new fluorinated anionic surfactant Cl（CF2）6O（CF2）2SO3N（C2H5）4 was prepared and characterized. The application of the fluorosurfactant allowed the fluoroalkylation to occur in the water without adding organic solvent. The addition of perfluoroalkyl iodides with olefins and alkynes under the initiation of Na2S2O4 in water in the presence of the fluorosurfactant gave the corresponding adducts in good to excellent yields. The fluorosurfactant was suitable for a radical addition process.
基金possible by grants from the Qatar National Research Fund under its National Priorities Research Program award number NPRP 6-729-2-301 and NPRP 8-1406-2-605
文摘This study investigates the removal of arsenite（As（III）） from water using dithionite activated by UV light. This work evaluated the removal kinetics of As（III） under UV light irradiation as affected by dithionite dose and light intensity, and characterized the nature of the precipitated solids using XPS and SEM-EDS. Photolysis of dithionite was observed by measuring dithionite concentration using UV absorbance at 315 nm. This study also investigated the effect of UV light path length on soluble As concentrations to understand resolubilization mechanisms. Total soluble As concentrations were observed to decrease with reaction time due to reduction of arsenite to form solids having a yellow-orange color.The removal mechanism was found to be reductive precipitation that formed solids of elemental arsenic or arsenic sulfide. However, these solids were observed to resolubilize at later times after dithionite had been consumed. Resolubilization of As was prevented and additional As removal was obtained by frequent dosing of dithionite throughout the experiment. As（III） removal is attributed to photolysis of dithionite by UV light and production of reactive radicals that reduce As（III） and convert it to solid forms.
基金This research work is supported by the National Natural Science Foundation of China (Grant No. 29902001) and the Department of Education of China.
文摘A novel synthesis of polyfluoroalkyl substituted -butyrolactones from the reaction of polyfluoroalkyl iodides with 4-pentenoic acid initiated with sodium dithionite was realized in good yields.
文摘Bleaching of the kaolin ore from Shaziling Kaolin Mine in Jiangxi Province of China was studied with the aim of enhancing the quality and value of the ore to meet the requirements from the ceramics manufacturers. Factors affecting the reductive bleaching of kaolin ore with sodium dithionite as the bleaching agent were studied and optimized to increase the whiteness of the kaolin ore from 38. 5% to about 65%. However, it was found that in the conventional bleaching process, a washing step to remove the ferrous ions from the bleached kaolin suspension was indispensable, which made the process complicated and restricted the capacity of the production. In addition, the whiteness of the bleached kaolin products was unstable. To solve the above problems, a new technique with the application of chelating agents in the bleaching process was developed to remove ferrous ions and get rid of the washing step. The bleaching process of kaolin was simplified. The whiteness of the bleached kaolin products was stabilized as well as increased to about 70%. The mechanism of the bleaching process and the action of the chelating agents were discussed.
基金Project supported by the National Natural Science Foundation of China （No. 20572079）, the Natural Science Foundation of Zhejiang Province （Nos. Y205540 and Y404039） and the Wenzhou University Postgraduate Innovation Foundation （No. YCX0514）.
文摘Reduced species （HSO2^-, SO2^·-） promoted one-pot synthesis of phenyl alkyl selenides has been developed. This synthetic method was achieved by reactions of diphenyl diselenide with alkyl halides at room temperature. It is noteworthy that the reactions were operated under mild reaction conditions, required short time, and got good resuits. A single electron transfer reaction mechanism was proposed for the reaction.
