Reactions of thermally generated tert-butyl and di(tert-alkyl) ketyl radicals in toluene: cage effects and hydrogen transfer

Thermolysis of di(1-adamantyl)-tert-butylmethanol (2a) in toluene at 145-185 o C gives mainly bibenzyl, di(1-adamantyl) ketone, di(1-adamantyl) methanol, and the cross-product, 1,1-di(1-adamantyl)-2-phenylethanol. In the presence of benzophenone (BP) or benzenethiols as hydrogen-accepting and hydrogen-donating radical scavengers, respectively, the di(1-adamantyl) methanol/di(1-adamantyl) ketone ratio tends to steady values as the scavenger/2a ratio is increased, while the cross-product disappears. At 165 o C the secondary alcohol minimum is 8% (BP) and the ketone minimum 11% (thiol)