Selective Vicinal Diiodination of Polycyclic Aromatic Hydrocarbons

Abstract

Vicinally diiodinated polycyclic aromatic hydrocarbons (I 2 ‐PAHs) are accessible from the corresponding diborylated B 2 ‐PAHs through boron/iodine exchange. The B 2 ‐PAHs have been prepared via twofold electrophilic borylation reactions templated by a vicinally disilylated benzene. Our protocol is applicable to fluorenes, acenes, annulated acenes, oligoaryls, and even [5]helicene. Using B 2 ‐naphthalene as the example, we have shown that the reaction scope can, in principle, be expanded to include the synthesis of vicinally dibrominated and dihydroxylated PAHs. The usefulness of the building blocks provided by our method in the field of optoelectronic materials was demonstrated by the successful conversion of I 2 ‐fluoranthene to the analogous doubly alkynylated fluoranthene emitter.