Benzynes have been used in organic synthesis in cycloaddition reactions to synthesize polycyclic aromatic compounds. But the regioselectivities of the reactions are generally quite low. Recently, we have reported the regioselective Diels-Alder reactions of benzynes substituted by a boryl or a silyl group at the 3-position with substituted furans. We have observed some different selectivities in the Diels-Alder reactions between silylbenzynes and borylbenzynes. On the other hand, we have just developed the regioselective [3+2] cycloadditions of silylbenzynes and borylbenzynes and these benzynes complement each other in these reactions.
In this conference, we are going to present results of the theoretical studies of regioselectivities in the cycloaddition reactions of boryl- and silylbenzynes. Transition states of the cycloaddition reactions optimized by B3LYP/6-31G(d) successfully explain the regioselectivities of the cycloaddition products.
