Regioselective photostimulated homolytic tert-butylations for heteroaromatics such as pyridines or thiophenes are investigated with tert-butylmercury (II) chloride in the presence of toluene-p-sulfonic acid (PTSA) or 1, 4-diazabicyclo [2.2. 2] octane (DABCO) respectively. While the promotion effect of acid is quite strong for basic pyridines, the acid does not promote the reaction effectively for non-basic thiophenes. On the other hand, pyridines ...
