ISSN:
0538-8066
Keywords:
Chemistry
;
Physical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The metathesis reaction of DI with t-C4H9 generated by 351-nm photolysis of 2,2′-azoisopropane was studied in a low-pressure reactor (VLPφ Knudsen cell) in the temperature range of 302-411 K. The data obeyed the following Arrhenius relation when combined with recent data by Rossi and Golden gathered by the same technique (t-C4H9 by thermal decomposition of 2,2′-azoisobutane): log k2D(M-1s-1) = 9.60 - 1.90/θ, where θ = 2.303RT kcal/mol for 302 K 〈 T 〉 722 K. The metathesis reaction of HI with t-C4H9 was studied at 301 K and resulted in k2H(M-1·s-1) = (3.20 ± 0.62) × 108. An analogous Arrhenius relation was calculated for the protiated system if the small primary isotope effect k2H/k2D was assumed to be √2 at 700 K. It was of the following form: log k2H(M-1·s-1) = 9.73 - 1.68/θ.Preliminary data of Bracey and Walsh indicate that earlier Arrhenius parameters determined for the reverse reaction are somewhat in error. Their value of log k1(M-1·s-1) = 11.5 - 23.8/θ yields 7delta;Hf,3000(t-butyl) = 9.2 kcal/mol and S3000(t-butyl) = 74.2 cal/mol7°K when taken in conjuction with this study.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/kin.550151204
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