REACTIONS OF RECOIL CARBON ATOMS IN METHANOL AND ETHANOL

Carbon-11 was produced by the reaction 12C(γ,n)11C in liquid methanol and ethanol, and the labeled products were separated and determined by radio-gas chromatography. A wide variety of products was observed from both alcohols. In the case of methanol mechanisms are proposed for their formation on the basis of the effect of change in dose and presence of I2 or DPPH scavenger. Without scavenger many products result from reaction of the 11C-containing intermediates with radicals observed in the radiation chemistry of methanol, particularly the hydroxy methyl radical, the hydrogen atom, and the solvated electron. Iodine scavenger effectively removes these radicals, and the product distribution can be explained on the basis of reactions of 11C, 11CH, and 11CH2 with the C-H and O-H bonds and of11C with a lone electron pair on oxygen. Iodine enters the reaction path by competition with the radiation-produced radicals, removing t em and in their place reacting with the 11C-containing intermediates. In several cases the products of these reactions react further with methanol to produce dialkoxyalkanes. The study of the ethanol system was less intensive; mechanisms proposed for this system are similar to those for methanol. © 1969, American Chemical Society. All rights reserved.