Photoinitiated carbonylation of alkyl iodides with [11C] carbon monoxide (11C t 1/2= 20.4 min) is enhanced by ketones that have lowest-lying excited triplet state of nπ* character. For example, adding 5 mol% of acetophenone increases radiochemical yields from 3 to 59% in brief 6-min long reactions. Similar or higher yields were achieved by adding di-tert-butyl peroxide. Since radicaloid nπ* exited-state ketones and tert-butoxyl radicals have similar ...
