
%0 Journal Article
%A Arthur, NL 
%A David, LF 
%T Reactions of trifluoromethyl radicals. III. Hydrogen abstraction from methyl trifluoroacetate, methyl pentafluoropropionate and methyl heptafluorobutyrate
%J Australian Journal of Chemistry
%D 1974/02/01
%V 27
%N 2
%P 291-297
%K 
%R https://doi.org/10.1071/CH9740291
%U https://www.publish.csiro.au/paper/CH9740291 
%X Hydrogen abstraction from CF3COOCH3, C2F5COOCH3 and C3F7COOCH3 by CF3 radicals has been studied in the temperature range 100-210º. The rate constants, based on the value of 1013,36 cm3 mol-1 s-1 for the recombination of CF3 radicals, are given by (kn in cm3 mol-1s-1, E in kJ mol-1, R = 0.008314 kJ K-1 mol-1):     Logk1 = (10.81 ± 0.16)-(37.52 ± 1.27)/2.303RT    Logk2 = (10.93 ± 0.16)-(38.80 ± 1.32)/2.303RT    Logk3 = (11.24 ± 0.08)-(42.49 ± 0.63)/2.303RT    The reactivity of the methoxyl groups in these esters is less than those in HCOOCH3 and CH3COOCH3 by a factor of between 2 and 3. This can be explained in terms of intermolecular polar repulsion induced by the fluorine atoms in the esters and the CF3 radical. 
