356-18-3Relevant articles and documents
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Lacher,Buechler,Park
, p. 1014 (1952)
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Solomon,Dee
, p. 2790 (1964)
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Park,J.D.,Frank,W.C.
, p. 1445 - 1449 (1964)
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Bimolecular kinetic studies with high-temperature gas-phase 19F NMR: Cycloaddition reactions of fluoroolefins
Shtarov,Krusic,Smart,Dolbier Jr.
, p. 9956 - 9962 (2007/10/03)
A gas-phase NMR kinetic technique has been used for the first time to obtain accurate measurements of rate constants of some bimolecular, second-order cycloaddition reactions. As a test of the potential use of this technique for the study of second-order reactions, the rate constants and the activation parameters for the cyclodimerization reactions of chlorotrifluoroethylene (CTFE) and tetrafluoroethylene (TFE) were determined in the temperature range 240-340 °C, using a commercial high-temperature NMR probe. Obtaining excellent agreement of the results with published data, the technique was then applied to the reaction of 1,1-difluoroallene with 1,3-butadiene, the results of which indicate that the use of gas-phase NMR for reaction kinetics is particularly valuable when a reagent is available only in small amounts and in cases where there are several competing processes occurring simultaneously. The major processes observed in this reaction are regioselective [2+2] and [2+4] cycloadditions, whose rates and activation parameters were determined [k2=9.3×106 exp(-20.1 kcal mol-1/RT) L/mol-1 S-1 and k3=1.2×106 exp(- 18.4 kcal mol-1/RT) L/mol-1 S-1, respectively] in the temperature range 130-210 °C.
Syntheses with Halogen Derivatives of Thiophene and Benzothiophene
Raasch, Maynard S.
, p. 2151 - 2155 (2007/10/02)
Pyrolysis of octachlorotetrahydrothiophene 1,1-dioxide provides a practical synthesis of octachlorocyclobutane. 1,2-Dichlorohexafluorotetrahydrothiophene 1,1-dioxide also yields a cyclobutane.Treatment of these sulfones with potassium hydroxide forms perhalogenated 3-butenesulfonates.From octachloro-2,3-dihydrobenzothiophene 1,1-dioxide, octachlorostyrene is produced by pyrolysis and hexachlorobenzothiophene 1,1-dioxide by treatment with sodium iodide.Hexachlorobenzothiophene has been prepared from octachloro-2,3-dihydrobenzothiophene and oxidized with chromium trioxide to a thiolactone (17).Hydrolysis of the latter gives a 2H-benzothiete (18).Oxidation of tetrachlorothiophene forms the thiolactone tetrachloro-2,3-dihydrothiophen-2-one (19).Octachlorodibenzothiophene can be made by direct chlorination.