LONG PATH FTIR SPECTROSCOPIC STUDY OF THE REACTIONS OF CF3O RADICALS WITH ALKENES

The reactions of CF3O radicals with alkenes have been studied using the long path FTIR method in the visible (lambda greater-than-or-equal-to 400 nm) photolysis of mixtures containing CF3NO, NO, and alkene (in milliTorr range) in 700 Torr of 02/N2 at 297 +/- 2 K. Kinetic and spectroscopic evidence has been obtained for the occurrence of the addition reaction (a) CF3O. + > C=C < --> adduct, and the subsequent reactions involving the adducts, for several alkenes. Using the reaction (b) CF3O. + NO --> CF2O + FNO as the reference reaction, values for the relative rate constants k(a)/k(b) have been determined to be 0.7 +/- 0.2(sigma), 0.9 +/- 0.2(sigma), 1.1 +/- 0.3(sigma), and 1.7 +/- 0.4(sigma) for CH2=CH2, CH3CH=CH2, trans-CH3CH=CHCH3, and (CH3)2C=C(CH3)2, respectively. Using the value of the rate constant for reaction b recently reported by Bavilacqua et al.4 (k(b) = (2 +/- 1) X 10-(11) cm3 molecule-1 s-1), the values of the rate constants k(a) have been calculated to be (1.4 +/- 0.8) X 10(-11), (1.8 +/- 1.0) X 10(-11), (2.2 +/- 1.3) X 10(-11), and (3.4 +/- 1.9) X 10(-11) cm3 molecule-1 s-1 for CH2=CH2, CH3CH2=CH2, trans-CH3CH=CHCH3, and (CH3)2C=C(CH3)2, respectively.