10.1021/jo0526744.s001 Pawel Rempala Pawel Rempala Jiří Kroulík Jiří Kroulík Benjamin T. King Benjamin T. King Investigation of the Mechanism of the Intramolecular Scholl Reaction of Contiguous Phenylbenzenes American Chemical Society 2006 Scholl reaction mass balance experiments Intramolecular Scholl Reaction bond generation Contiguous PhenylbenzenesTwo mechanisms arenium cation MoCl 5 formation FeCl 3 Reaction optimization studies Kinetic simulations dehydrogenation activation energies arenium cation mechanism B 3LYP level 2006-07-07 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Investigation_of_the_Mechanism_of_the_Intramolecular_Scholl_Reaction_of_Contiguous_Phenylbenzenes/3071875 Two mechanisms of the Scholl reaction were investigated in the series 1, 2, ..., <i>n</i>-oligophenylbenzenes (<i>n</i> = 2, 3, 4, 6) at the B3LYP/6-31G(d) level of theory. A mechanism involving generation of a radical cation followed by C−C bond formation and dehydrogenation is unlikely on the basis of unfavorable energies of activation. A mechanism involving generation of an arenium cation followed by C−C bond formation and dehydrogenation is energetically feasible. An explanation for the facile polycondensation of hexaphenylbenzene to hexa-<i>peri</i>-hexabenzocoronene, where six new aryl−aryl bonds are formed, is provided. Kinetic simulations based on the calculated activation energies of the arenium cation mechanism predict that intermediates will not accumulate; this is supported by mass balance experiments. Reaction optimization studies suggest that PhI(O<sub>2</sub>CCF<sub>3</sub>)<sub>2</sub>/BF<sub>3</sub>·OEt<sub>2</sub> or MoCl<sub>5</sub> are superior to FeCl<sub>3</sub> or AlCl<sub>3</sub>/CuCl<sub>2</sub>. This is a full account of our work reported partially as a communication previously (Rempala, P.; Kroulík, J.; King, B. T. <i>J. Am. </i><i>Chem. Soc.</i> <b>2004</b>, <i>126</i>, 15002−15003).