4786 lip, cm-l. 0.2
0.4
0.6
preliminary form, and Professors F. S. Rowland and D. W. Setser for prepublication copies of their manuscripts.
0.8
(24) A referee has observed that the disproportionation between any radical (CFZH, CD3, CDZCOCDI, CFZCOCFZH)in the system and CFzH will yield CFZand that the reaction sequence
CF2
+ C D C O C D , +(CFZCD~COCD~)* + CFZCDI
+ COCDB
accounts for the CFZCDZ. We make the following points. (a) Probably only the self-disproportionation us. recombination of 0.1 r I I I I CFzH's ( k d / k , ) is important, and is equal to 0.19;e values of k,i/k, 0.1 0.2 0.3 (to give CR) are for CFHz f CFZH = 0.06,o for CF3 CFzH = 0.09 1 fl, cm-1. (M. J. Perona and G. 0. Pritchard, to be published), and for CH3 CF?H = 0.'' The fate of the CFZhas been difficult to establish unFigure 5 . Plot of Re1imimarirn/Rstai,iiiration us. 116 (see Figure 2): equivocally,s but fluoropropanes, from combinatiorr with monoradicals, been observed (M. G. Bcllas, 0. P. Strausz, and H. E. 0, RCF~-CD~/RCF~HCD~ at 240"; 0 and 0 , R c F ~ = c ~ ~ / atR 145 c F ~ ~ have c ~ ~recently ~ Gunning, Can. J . Chem., 43, 1022 (1965); J. B. Hynes, R. C. Price, and 188", respectively. W. S. Brey, Jr., M. J. Perona, and G. 0. Pritchard, ibid., 45,2278 (1967); and to be published). (b) A pathway involving CFz cannot be ruled out, and, where we conThe evidence that we have presented strongly suggests ducted analysis for CzF CFzCD?. Simi~ the participation of acetonyl larly 0.19C?F,H? > C F I C H Z . ' ~However, that the "hot" molecule CF2HCD3*may decompose by radicals cannot be assumed under all of our reaction conditions, altwo, and probably three, competing unimolecular prothough CFKDz is formed under all conditions. I n our previous lowcesses. 2 4 A complete understanding of this complex pressure experimcnts,G abstraction from the fluoroacetones was negligible up to 500"I
