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Selective monoaddition of carbonodithioate anions to divinyl sulfoxide gives rise to O-alkyl S-[2-(vinylsulfinyl)ethyl] carbonodithioates [ROC(S)SK, R = Et, Bu; 42–50°C, 6 h, NaHCO3, aqueous benzene].  相似文献   
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The reaction of methyl-2-selenienylketoxime with acetylene in KOH-DMSO gives 2-(2-selenienyl)pyrrole and its 1-vinyl derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 708–710, May, 1992.  相似文献   
4.
High-Temperature Synthesis of Thiophene from Bis(2-chloroethyl) Sulfide   总被引:1,自引:0,他引:1  
Gas-phase reaction of bis(2-chloroethyl) sulfide (Yperite) with acetylene at 550–700°C leads to formation of thiophene in 45% yield, the conversion of the initial sulfide being complete. The yield of thiophene reaches 63–68% in the thermolysis of a mixture of acetylene, bis(2-chloroethyl) sulfide, and lower organic disulfides.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 910–912.Original Russian Text Copyright © 2005 by Voronkov, Levanova, Sukhomazova, Russavskaya, Deryagina, Korchevin.  相似文献   
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Dimethyldiselenide reacts with 2,3-dichloro-1-propene at 20–25°C in the hydrazine hydrate-KOH medium to form 2-chloro-3-methylselanyl-1-propene with 90% yield. Diphenyldiselenide in the reaction with 2,3-dichloro-1-propene, depending on the conditions, can give quite selectively four products: 2-chloro-3-phenylselanyl-1-propene, phenylselanylpropadiene, 1-phenylselanyl-1-propyne, and Z-1,2-bis(phenylselanyl)-1-propene. The effect of the selenium atom on the reaction direction and the products structure is discussed.  相似文献   
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Russian Journal of General Chemistry - A possibility of the synthesis of 1,4-dichalcogenins by the reaction of vinylidene chloride or 1,2-dichloroethene with elemental chalcogenes in a hydrazine...  相似文献   
8.
Dibenzyldisulfide and -diselenide react with 2,3-dichloro-1-propene in the system hydrazine hydrate-KOH by the domino mechanism: nucleophilic substitution of the allyl chlorine, dehydrochlorination with participation of the chlorine atom at the sp 2-carbon atom, allene-acetylene rearrangement, nucleophilic addition of the chalcogenide reagent to the triple bond. The effect of the nature of the chalcogen atom and the benzyl substituent on the studied domino reaction is discussed.  相似文献   
9.
The saturated heterocyclic compounds C4H8Y, C5H10Y, and C5H10Y2 (Y = Se or Te) have been prepared by the reaction of 1,4-dibromobutane or 1,5-dibromopentane with potassium chalcogenides. The novelty of the route consists of the use of the hydrazine hydrate–KOH system for the reductive generation of potassium selenide, telluride, diselenide or ditelluride from elemental chalcogens.  相似文献   
10.
Thermal gas-phase reactions of acrolein, cinnamaldehyde, and benzaldehyde with diorganyl chalcogenides and diorganyl dichalcogenides were studied. Acrolein does not react with chalcogenides at 300–600°C but completely decomposes under reaction conditions. At 600–650°C, cinnamaldehyde reacts only with diorganyl selenides and diselenides to give benzoselenophene. Its highest yield (53%) is achieved in the reaction with dimethyl diselenide at 630°C and at an equimolar ratio of the reactant. The gas-phase reactions of benzaldehyde at 400–500°C afford chalcogen-containing derivatives of several types, among which thioanisole and its selenium or tellurium analogs predominate. The mechanisms of the above reactions were discussed in terms of homolytic substitution of the formyl group at unsaturated carbon atoms by chalcogenyl radicals.  相似文献   
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