The reaction of CzF5 radicals with HzS (2) C2F5 + HzS -+ CzF5H + HS kfi was studied over the range 1"-123"C using CZFS radicals generated by photolysis of perfluoropropionic anhydride. The rate constant k~ for reaction (2) is given by where e = 2.303RT/cal mole-'. The relevance of this result to c
The reactions of C2F5 radicals with benzene in the vapor phase
โ Scribed by G. A. Chamberlain; E. Whittle
- Publisher
- John Wiley and Sons
- Year
- 1972
- Tongue
- English
- Weight
- 355 KB
- Volume
- 4
- Category
- Article
- ISSN
- 0538-8066
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โฆ Synopsis
C2F5 radicals were generated in the presence of benzene vapor by the reaction (C2FsCO)20 + hv -+ CO + C02 + 2CzFs
The radicals react with the benzene by addition and pseudo H abstraction
The rate constant k a d d for the addition reaction ( 7) is given by
where e = 2.303RT cal/mole and k , is the rate constant for combination of C2F5 radicals. The addition becomes reversible above 110ยฐC. The reactions of CF3 and CzF5 radicals with benzene vapor are compared.
๐ SIMILAR VOLUMES
A mixture of Brz + HBr + CzFsI was photolyzed in the vapor phase. The reaction Br + CzFsI -IBr + CzF5 forms CzFb radicals which are removed by (9) CzFs + Brz -CzFbBr + Br kg (10) CzFs + HBr -CzFsH + Br klo Competitive studies over the range of 74-146'C gave ratios of h l ~/ h s , and these were comb
CF3 radicals were generated by the photolysis of perfluoroacetic anhydride. In the presence of pentafluorobenzene, the CF3 radicals react according to the following mechanism: It was found that the addition reaction (3) becomes reversible above ca. 453 K. The addition rate parameters have been rev
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A rate constant for the epoxidation of acrolein by acetylperoxyl radicals has been determined to be k 4 ฯญ (1.3 ฯฎ 0.9) ฯซ 10 4 dm 3 mol ฯช1 s ฯช1 at 383 K, which is anomalously fast in comparison with the epoxidation of alkenes. Abstraction of the acyl hydrogen atom from acrolein by acetylperoxyl radica
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