Synthesis of Fluoranthene Derivatives via Tandem Suzuki-Miyaura and Intramolecular C-H Arylation Reactions under Both Homogeneous and Heterogeneous Catalytic Conditions.

A catalytic method for the synthesis of substituted fluoranthenes that operates via tandem Suzuki-Miyaura and intramolecular C-H arylation reactions is reported. The overall reaction sequence works effectively with homogeneous catalysis using Pd(dppf)Cl as well as heterogeneous catalysis using reduced graphene oxide (rGO)-CuPd nanocatalysts with low catalyst loadings. High functional group tolerance is observed under both catalytic conditions where arylboronic acids and esters having electron-withdrawing and electron-donating substituents afforded fluoranthene products in good yields (up to 78%). Moreover, the rGO-CuPd nanocatalysts are demonstrated to be reusable by preserving almost 90% of their initial activity after the third cycle.