| Abstract
| - We report an easy access to the salts of the LiC(BMe)11- anion, which greatly simplifies thesynthesis of compounds carrying the −C(BMe)11- substituent, including the title anions. The previouslyrecognized and puzzling spontaneous oligomerization of the solid lithium salts CH2CH(CH2)n-2C(BMe)11- Li+upon storage under ambient conditions is now shown to proceed by a radical mechanism, with the “naked”Li+ cation acting as a catalyst. The degree of polymerization is higher in solution, especially whenazoisobutyronitrile (AIBN) is used as initiator (up to ∼50). Initiation by the thermal decomposition of AIBNis also catalyzed by naked Li+, and this initiator is effective at room temperature. Di-tert-butyl peroxide andUV irradiation can also be used. The observation of Li+ catalysis agrees with a prior prediction from abinitio calculations, according to which Li+ complexation of ethylene strongly lowers the activation energyfor methyl radical addition. The results bear on the current discussion of the possible sensitivity of radicalclocks to their molecular environment and suggest that naked Li+ will catalyze the radical polymerizationof simple terminal alkenes.
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